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AN/URQ-13 FE-15a oscillator question

BK
Bob kb8tq
Sat, Feb 13, 2021 2:14 PM

Hi

What frequency is it putting out?

Bob

On Feb 12, 2021, at 9:45 PM, paul swed paulswedb@gmail.com wrote:

I see a glass tape on the inner oven with writing "40.0". Thats it.
Assuming C its a long way off.The flask is fine the ovens are heating to
110F. Both of them. So somethings wrong. Interesting as I peel something
like caulking off the outer board I see what looks like a opamp. But its a
FE house number. The top of the can has NSC. The old national semiconductor
label. Could be a LM709 class opamp.

On Fri, Feb 12, 2021 at 9:12 PM Bob kb8tq kb8tq@n1k.org wrote:

Hi

If you are reading something below 60C on a dewar flask outer oven …. it
is borken….. very broken.

Bob

On Feb 12, 2021, at 7:25 PM, paul swed paulswedb@gmail.com wrote:

The temps I am reading are with a K thermocouple so pretty accurate. I

had

simply slid the thermocouple into the flask on the outer edge of the
ovens.The assembly is out of the flask now and both inner and outer are
heating. Will see what they do. Both seem to be heating at about the same
rate. So the great news is the oven windings are not bad. I do see a very
significant voltage difference on two leads that I might guess matter.

But

still decoding and reverse engineering everything.

On Fri, Feb 12, 2021 at 5:20 PM Bob kb8tq kb8tq@n1k.org wrote:

Hi

According to table 1-2 in:

http://www.navy-radio.com/freq/urq-eimb.pdf <
http://www.navy-radio.com/freq/urq-eimb.pdf>

The URQ-9 and URQ-10 both were rated for 0 to 50C.

Per:

http://www.navy-radio.com/freq/urq23-MIL-T-28816.pdf <
http://www.navy-radio.com/freq/urq23-MIL-T-28816.pdf>

The URQ-23 was rated for 0 to 50C

I’d say it’s a pretty likely that the URQ-13 was rated to operate over
0 to 50C. It went into the same locations and did the same thing as the
other devices.

Bob

On Feb 12, 2021, at 1:07 PM, paul swed paulswedb@gmail.com wrote:

Well there is no doubt someone has been deep into this unit. Hint

missing

screws internally.
But appears both heater windings are ok.
So inner and outer oven has a new meaning. I typically understood this

to

be one oven in another oven. Think the HP CS units of old. The same in
other places HP3801.
But in the URQ13 it means there is a long tube. The Dewar flask. The

inner

is deep into the flask and the outer is close to the opening. Two
completely separate heaters. Under the outer heater I will guess is the
actual oscillator for the 5 MHz. Further out from the outer heater are

the

offset variable caps thermistor for the outer oven a pot and IC.
Several screws hold this outer heater on and considering the risk of

taking

out the remainders to look and draw a schematic.
Regards
Paul

On Fri, Feb 12, 2021 at 11:28 AM paul swed paulswedb@gmail.com

wrote:

Yes Bob they could get hot. But the radio rooms I have been in circa

1970s

were all air conditioned from destroyers to aircraft carriers. Shirt
sleeve. The best place to actually be when we were down by the equator

was

the radio room, ET shop, CIC and radar and just maybe the Captain's
stateroom. But if you were actually there you might still be sweating.
Chuckle.
This conversation has given me some good insights. Later today I will
disable the outer oven. Just curious to see what possible temps might

show

up. Is the inner oven simply reading outer oven leakage. Is there a

lead I

can measure the current of the inner oven....
Thanks

On Fri, Feb 12, 2021 at 11:18 AM Bob kb8tq kb8tq@n1k.org wrote:

Hi

If it’s 105F “outdoors” that’s 40C. Military gear back in the days of

the

URQ10
did not live in air conditioned enclosures. It did get deployed to

places

with
temperatures at or above that level.

If it’s 40C outdoors, by the time you get to a pile of electronics

gear

indoors,
a >10C rise is pretty likely. That drives a very common 50C “upper

end”

temperature
on ground gear in relatively benign installations.

This does not just apply to military gear. If you look through test
equipment
catalogs, a lot of test gear also has the same sort of 50 to 60C

upper

end spec.
The 5065A has a spec of 0 to 50C. The 5061A has the same spec. Both
targeted
pretty “normal” environments …. ( = they never get below freezing …)

and

date
to the “era” of the URQ10.

In this era of HVAC everywhere, the 5071A has a temp range of 0 to

55C.

If
anything, this would suggest that things still can get pretty hot.

Bob

On Feb 12, 2021, at 10:29 AM, paul swed paulswedb@gmail.com

wrote:

Bob
OK there is the math. and that all starts to line up.
So most likely for other URQ units there will be an ambient max in

the

spec's. At least on the URQ10 in real life even in the hot tropics

the

radio room was shirt sleeve temps.
But the question asked was 110 F correct as measured on the outside

of

the

outer oven against the dewar flask correct. It isn't. The darn thing

is

reasonably stable though.
Since the front panel test switch is not labeled I speculate that

the

position for the outer oven is in the normal range. The next switch
position most likely is inner and is not in the correct position. It

slowly

moves to the high side.
No real details on anything and a total guess.
Really appreciate the thoughts.
Regards
Paul
WB8TSL

On Fri, Feb 12, 2021 at 10:18 AM Bob kb8tq kb8tq@n1k.org wrote:

Hi

Indeed the outer oven (as a minimum) needs to be 5 to 10 C above
the maximum ambient. If it’s not it goes out of regulation (runs

away)

and you loose any benefit from it. ( = it now works against you ).

The inner oven as a minimum needs to be 5 to 10 C above the outer
oven. Again if it is lower, you can / will get into the same

runaway

issue.

Those offsets are dependent on the way things are insulated. If you

are

using a dewar flask, 5C is probably not going to work for you.

Your inner oven also is impacted by the turn temperature on the

crystal

being used. This might have a 20C range. That would put the

maximum

inner oven temperature at 10 + 10 + 20 = 40C above the maximum

ambient.

Needless to say, if the max ambient is 85C, this will get the inner

oven

components up pretty hot. That’s not a real good idea. Derating the

heater

is pretty easy, derating everything in there is much more

complex.

You

do not often see 85C upper end double ovens ….

One could also ask: “is all this worth it?”. List members have

written

papers addressing that point :)

Bob

On Feb 11, 2021, at 10:05 PM, Paul Alfille <

wrote:

Shouldn't the outer oven be cooler than the inner oven except

during

warmup? I would think the inner electronics would be generating

heat.

Paul Alfille K1PHA

On Thu, Feb 11, 2021 at 9:30 PM paul swed paulswedb@gmail.com

wrote:

50C is what I have sort of seen over the years. Just wondered

could

there

have been a lower temp version. That made no sense. But then this

beast

has

never made a lot of sense. The $20 mystery from Frequency

Electronics.

Thanks Bob
Paul
WB8TSL

On Thu, Feb 11, 2021 at 8:08 PM Bob kb8tq kb8tq@n1k.org wrote:

Hi

Even for an outer oven, anything below 60C / 140F would be low

enough

to

run into significant problems. On a mil device, an upper end

temperature

on
the equipment likely would be over 70C. The outer oven would

need

to be

5 to 10C above that.

Bob

On Feb 11, 2021, at 5:55 PM, paul swed paulswedb@gmail.com

wrote:

OK I have had several responses and 110F is low as I expected.
Wonder if I am being faked out? Perhaps by an inner oven and I

am

only

reading the outside of the outer oven. The Older URQ10 and

newer

URQ23

do

have 2 ovens. The meter switch for test is only labeled 1-9. no

other

clues

to the function. I noticed 2 positions change with warm up.

Sort

of

supports the 2 oven theory.
Really do not want to take what might be the outer oven off to

put

the

probe in.
Thanks everyone.
Paul
WB8TSL

On Thu, Feb 11, 2021 at 5:32 PM Bob kb8tq kb8tq@n1k.org

wrote:

Hi

110 F makes very little sense unless you are in a very cold

climate.

For military gear (or any gear for that matter) 43C on the

oven

just

doesn’t work.

110 C would make sense in a very high temperature environment.
(think of 85C upper end ….).

Bob

On Feb 11, 2021, at 2:18 PM, paul swed paulswedb@gmail.com

wrote:

Hello to the group.
I have had a AN/URQ-13 or FE-15a oven oscillator for years.
Its never worked correctly and in reality some early alpha

build.

(Funny

that its labeled 15a)
Looking online there is no documentation that I have been

able

to

find

over

the years.
However in another discussion on a AN/URQ-23 that does have a

manual

and

schematics I realized my guesses on power could be totally

wrong.

Using

voltages like the URQ23 the URQ13 actually behaves fairly

well. I

was

lucky

that I didn't destroy something with my original guess.
That said what I find odd is the internal crystal oven runs

at

exactly

110

degrees. Its repeatably warms to that level with a range of

supply

from

+/-

12-15V.
Does 110 degrees F make any sense at all?
Thank you
Paul
WB8TSL


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Hi What frequency is it putting out? Bob > On Feb 12, 2021, at 9:45 PM, paul swed <paulswedb@gmail.com> wrote: > > I see a glass tape on the inner oven with writing "40.0". Thats it. > Assuming C its a long way off.The flask is fine the ovens are heating to > 110F. Both of them. So somethings wrong. Interesting as I peel something > like caulking off the outer board I see what looks like a opamp. But its a > FE house number. The top of the can has NSC. The old national semiconductor > label. Could be a LM709 class opamp. > > On Fri, Feb 12, 2021 at 9:12 PM Bob kb8tq <kb8tq@n1k.org> wrote: > >> Hi >> >> If you are reading something below 60C on a dewar flask outer oven …. it >> is borken….. very broken. >> >> Bob >> >>> On Feb 12, 2021, at 7:25 PM, paul swed <paulswedb@gmail.com> wrote: >>> >>> The temps I am reading are with a K thermocouple so pretty accurate. I >> had >>> simply slid the thermocouple into the flask on the outer edge of the >>> ovens.The assembly is out of the flask now and both inner and outer are >>> heating. Will see what they do. Both seem to be heating at about the same >>> rate. So the great news is the oven windings are not bad. I do see a very >>> significant voltage difference on two leads that I might guess matter. >> But >>> still decoding and reverse engineering everything. >>> >>> On Fri, Feb 12, 2021 at 5:20 PM Bob kb8tq <kb8tq@n1k.org> wrote: >>> >>>> Hi >>>> >>>> According to table 1-2 in: >>>> >>>> http://www.navy-radio.com/freq/urq-eimb.pdf < >>>> http://www.navy-radio.com/freq/urq-eimb.pdf> >>>> >>>> The URQ-9 and URQ-10 both were rated for 0 to 50C. >>>> >>>> Per: >>>> >>>> http://www.navy-radio.com/freq/urq23-MIL-T-28816.pdf < >>>> http://www.navy-radio.com/freq/urq23-MIL-T-28816.pdf> >>>> >>>> The URQ-23 was rated for 0 to 50C >>>> >>>> I’d say it’s a pretty likely that the URQ-13 was rated to operate over >>>> 0 to 50C. It went into the same locations and did the same thing as the >>>> other devices. >>>> >>>> Bob >>>> >>>> >>>>> On Feb 12, 2021, at 1:07 PM, paul swed <paulswedb@gmail.com> wrote: >>>>> >>>>> Well there is no doubt someone has been deep into this unit. Hint >> missing >>>>> screws internally. >>>>> But appears both heater windings are ok. >>>>> So inner and outer oven has a new meaning. I typically understood this >> to >>>>> be one oven in another oven. Think the HP CS units of old. The same in >>>>> other places HP3801. >>>>> But in the URQ13 it means there is a long tube. The Dewar flask. The >>>> inner >>>>> is deep into the flask and the outer is close to the opening. Two >>>>> completely separate heaters. Under the outer heater I will guess is the >>>>> actual oscillator for the 5 MHz. Further out from the outer heater are >>>> the >>>>> offset variable caps thermistor for the outer oven a pot and IC. >>>>> Several screws hold this outer heater on and considering the risk of >>>> taking >>>>> out the remainders to look and draw a schematic. >>>>> Regards >>>>> Paul >>>>> >>>>> On Fri, Feb 12, 2021 at 11:28 AM paul swed <paulswedb@gmail.com> >> wrote: >>>>> >>>>>> Yes Bob they could get hot. But the radio rooms I have been in circa >>>> 1970s >>>>>> were all air conditioned from destroyers to aircraft carriers. Shirt >>>>>> sleeve. The best place to actually be when we were down by the equator >>>> was >>>>>> the radio room, ET shop, CIC and radar and just maybe the Captain's >>>>>> stateroom. But if you were actually there you might still be sweating. >>>>>> Chuckle. >>>>>> This conversation has given me some good insights. Later today I will >>>>>> disable the outer oven. Just curious to see what possible temps might >>>> show >>>>>> up. Is the inner oven simply reading outer oven leakage. Is there a >>>> lead I >>>>>> can measure the current of the inner oven.... >>>>>> Thanks >>>>>> >>>>>> On Fri, Feb 12, 2021 at 11:18 AM Bob kb8tq <kb8tq@n1k.org> wrote: >>>>>> >>>>>>> Hi >>>>>>> >>>>>>> If it’s 105F “outdoors” that’s 40C. Military gear back in the days of >>>> the >>>>>>> URQ10 >>>>>>> did not live in air conditioned enclosures. It did get deployed to >>>> places >>>>>>> with >>>>>>> temperatures at or above that level. >>>>>>> >>>>>>> If it’s 40C outdoors, by the time you get to a pile of electronics >> gear >>>>>>> *indoors*, >>>>>>> a >10C rise is pretty likely. That drives a very common 50C “upper >> end” >>>>>>> temperature >>>>>>> on ground gear in relatively benign installations. >>>>>>> >>>>>>> This does not just apply to military gear. If you look through test >>>>>>> equipment >>>>>>> catalogs, a lot of test gear also has the same sort of 50 to 60C >> upper >>>>>>> end spec. >>>>>>> The 5065A has a spec of 0 to 50C. The 5061A has the same spec. Both >>>>>>> targeted >>>>>>> pretty “normal” environments …. ( = they never get below freezing …) >>>> and >>>>>>> date >>>>>>> to the “era” of the URQ10. >>>>>>> >>>>>>> In this era of HVAC everywhere, the 5071A has a temp range of 0 to >> 55C. >>>>>>> If >>>>>>> anything, this would suggest that things still can get pretty hot. >>>>>>> >>>>>>> Bob >>>>>>> >>>>>>>> On Feb 12, 2021, at 10:29 AM, paul swed <paulswedb@gmail.com> >> wrote: >>>>>>>> >>>>>>>> Bob >>>>>>>> OK there is the math. and that all starts to line up. >>>>>>>> So most likely for other URQ units there will be an ambient max in >> the >>>>>>>> spec's. At least on the URQ10 in real life even in the hot tropics >> the >>>>>>>> radio room was shirt sleeve temps. >>>>>>>> But the question asked was 110 F correct as measured on the outside >> of >>>>>>> the >>>>>>>> outer oven against the dewar flask correct. It isn't. The darn thing >>>> is >>>>>>>> reasonably stable though. >>>>>>>> Since the front panel test switch is not labeled I speculate that >> the >>>>>>>> position for the outer oven is in the normal range. The next switch >>>>>>>> position most likely is inner and is not in the correct position. It >>>>>>> slowly >>>>>>>> moves to the high side. >>>>>>>> No real details on anything and a total guess. >>>>>>>> Really appreciate the thoughts. >>>>>>>> Regards >>>>>>>> Paul >>>>>>>> WB8TSL >>>>>>>> >>>>>>>> On Fri, Feb 12, 2021 at 10:18 AM Bob kb8tq <kb8tq@n1k.org> wrote: >>>>>>>> >>>>>>>>> Hi >>>>>>>>> >>>>>>>>> Indeed the outer oven (as a minimum) needs to be 5 to 10 C above >>>>>>>>> the maximum ambient. If it’s not it goes out of regulation (runs >>>> away) >>>>>>>>> and you loose any benefit from it. ( = it now works against you ). >>>>>>>>> >>>>>>>>> The inner oven as a minimum needs to be 5 to 10 C above the outer >>>>>>>>> oven. Again if it is lower, you can / will get into the same >> runaway >>>>>>>>> issue. >>>>>>>>> >>>>>>>>> Those offsets are dependent on the way things are insulated. If you >>>> are >>>>>>>>> using a dewar flask, 5C is probably not going to work for you. >>>>>>>>> >>>>>>>>> Your inner oven *also* is impacted by the turn temperature on the >>>>>>> crystal >>>>>>>>> being used. This *might* have a 20C range. That would put the >> maximum >>>>>>>>> inner oven temperature at 10 + 10 + 20 = 40C above the maximum >>>> ambient. >>>>>>>>> >>>>>>>>> Needless to say, if the max ambient is 85C, this will get the inner >>>>>>> oven >>>>>>>>> components up pretty hot. That’s not a real good idea. Derating the >>>>>>> heater >>>>>>>>> is pretty easy, derating *everything* in there is much more >> complex. >>>>>>> You >>>>>>>>> do not often see 85C upper end double ovens …. >>>>>>>>> >>>>>>>>> One *could* also ask: “is all this worth it?”. List members *have* >>>>>>> written >>>>>>>>> papers addressing that point :) >>>>>>>>> >>>>>>>>> Bob >>>>>>>>> >>>>>>>>>> On Feb 11, 2021, at 10:05 PM, Paul Alfille < >> paul.alfille@gmail.com> >>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>> Shouldn't the outer oven be cooler than the inner oven except >> during >>>>>>>>>> warmup? I would think the inner electronics would be generating >>>> heat. >>>>>>>>>> >>>>>>>>>> Paul Alfille K1PHA >>>>>>>>>> >>>>>>>>>> On Thu, Feb 11, 2021 at 9:30 PM paul swed <paulswedb@gmail.com> >>>>>>> wrote: >>>>>>>>>> >>>>>>>>>>> 50C is what I have sort of seen over the years. Just wondered >> could >>>>>>>>> there >>>>>>>>>>> have been a lower temp version. That made no sense. But then this >>>>>>> beast >>>>>>>>> has >>>>>>>>>>> never made a lot of sense. The $20 mystery from Frequency >>>>>>> Electronics. >>>>>>>>>>> Thanks Bob >>>>>>>>>>> Paul >>>>>>>>>>> WB8TSL >>>>>>>>>>> >>>>>>>>>>> On Thu, Feb 11, 2021 at 8:08 PM Bob kb8tq <kb8tq@n1k.org> wrote: >>>>>>>>>>> >>>>>>>>>>>> Hi >>>>>>>>>>>> >>>>>>>>>>>> Even for an outer oven, anything below 60C / 140F would be low >>>>>>> enough >>>>>>>>> to >>>>>>>>>>>> run into significant problems. On a mil device, an upper end >>>>>>>>> temperature >>>>>>>>>>>> on >>>>>>>>>>>> the equipment likely would be over 70C. The outer oven would >> need >>>>>>> to be >>>>>>>>>>>> 5 to 10C above that. >>>>>>>>>>>> >>>>>>>>>>>> Bob >>>>>>>>>>>> >>>>>>>>>>>>> On Feb 11, 2021, at 5:55 PM, paul swed <paulswedb@gmail.com> >>>>>>> wrote: >>>>>>>>>>>>> >>>>>>>>>>>>> OK I have had several responses and 110F is low as I expected. >>>>>>>>>>>>> Wonder if I am being faked out? Perhaps by an inner oven and I >> am >>>>>>> only >>>>>>>>>>>>> reading the outside of the outer oven. The Older URQ10 and >> newer >>>>>>> URQ23 >>>>>>>>>>> do >>>>>>>>>>>>> have 2 ovens. The meter switch for test is only labeled 1-9. no >>>>>>> other >>>>>>>>>>>> clues >>>>>>>>>>>>> to the function. I noticed 2 positions change with warm up. >> Sort >>>> of >>>>>>>>>>>>> supports the 2 oven theory. >>>>>>>>>>>>> Really do not want to take what might be the outer oven off to >>>> put >>>>>>> the >>>>>>>>>>>>> probe in. >>>>>>>>>>>>> Thanks everyone. >>>>>>>>>>>>> Paul >>>>>>>>>>>>> WB8TSL >>>>>>>>>>>>> >>>>>>>>>>>>> On Thu, Feb 11, 2021 at 5:32 PM Bob kb8tq <kb8tq@n1k.org> >> wrote: >>>>>>>>>>>>> >>>>>>>>>>>>>> Hi >>>>>>>>>>>>>> >>>>>>>>>>>>>> 110 F makes very little sense unless you are in a very cold >>>>>>> climate. >>>>>>>>>>>>>> For military gear (or any gear for that matter) 43C on the >> oven >>>>>>> just >>>>>>>>>>>>>> doesn’t work. >>>>>>>>>>>>>> >>>>>>>>>>>>>> 110 C would make sense in a very high temperature environment. >>>>>>>>>>>>>> (think of 85C upper end ….). >>>>>>>>>>>>>> >>>>>>>>>>>>>> Bob >>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Feb 11, 2021, at 2:18 PM, paul swed <paulswedb@gmail.com> >>>>>>> wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Hello to the group. >>>>>>>>>>>>>>> I have had a AN/URQ-13 or FE-15a oven oscillator for years. >>>>>>>>>>>>>>> Its never worked correctly and in reality some early alpha >>>> build. >>>>>>>>>>>> (Funny >>>>>>>>>>>>>>> that its labeled 15a) >>>>>>>>>>>>>>> Looking online there is no documentation that I have been >> able >>>> to >>>>>>>>>>> find >>>>>>>>>>>>>> over >>>>>>>>>>>>>>> the years. >>>>>>>>>>>>>>> However in another discussion on a AN/URQ-23 that does have a >>>>>>> manual >>>>>>>>>>>> and >>>>>>>>>>>>>>> schematics I realized my guesses on power could be totally >>>> wrong. >>>>>>>>>>> Using >>>>>>>>>>>>>>> voltages like the URQ23 the URQ13 actually behaves fairly >>>> well. I >>>>>>>>> was >>>>>>>>>>>>>> lucky >>>>>>>>>>>>>>> that I didn't destroy something with my original guess. >>>>>>>>>>>>>>> That said what I find odd is the internal crystal oven runs >> at >>>>>>>>>>> exactly >>>>>>>>>>>>>> 110 >>>>>>>>>>>>>>> degrees. Its repeatably warms to that level with a range of >>>>>>> supply >>>>>>>>>>> from >>>>>>>>>>>>>> +/- >>>>>>>>>>>>>>> 12-15V. >>>>>>>>>>>>>>> Does 110 degrees F make any sense at all? >>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>> WB8TSL >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com >>>>>>>>>>>>>>> To unsubscribe, go to >>>>>>>>>>>>>> >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>>>>>>>>>>>>> and follow the instructions there. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com >>>>>>>>>>>>>> To unsubscribe, go to >>>>>>>>>>>>>> >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>>>>>>>>>>>> and follow the instructions there. >>>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com >>>>>>>>>>>>> To unsubscribe, go to >>>>>>>>>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>>>>>>>>>>> and follow the instructions there. >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com >>>>>>>>>>>> To unsubscribe, go to >>>>>>>>>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>>>>>>>>>> and follow the instructions there. >>>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com >>>>>>>>>>> To unsubscribe, go to >>>>>>>>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>>>>>>>>> and follow the instructions there. >>>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com >>>>>>>>>> To unsubscribe, go to >>>>>>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>>>>>>>> and follow the instructions there. >>>>>>>>> >>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com >>>>>>>>> To unsubscribe, go to >>>>>>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>>>>>>> and follow the instructions there. >>>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com >>>>>>>> To unsubscribe, go to >>>>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>>>>>> and follow the instructions there. >>>>>>> >>>>>>> >>>>>>> _______________________________________________ >>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com >>>>>>> To unsubscribe, go to >>>>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>>>>> and follow the instructions there. >>>>>>> >>>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- time-nuts@lists.febo.com >>>>> To unsubscribe, go to >>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>>> and follow the instructions there. >>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- time-nuts@lists.febo.com >>>> To unsubscribe, go to >>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>> and follow the instructions there. >>>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@lists.febo.com >>> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>> and follow the instructions there. >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. >> > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there.
GH
Gerhard Hoffmann
Sat, Feb 13, 2021 3:43 PM

Hi, all of y'all,

would you please snip the cited parts that are long out of
context?!!one!eleven!!!!!!

I wonder how that reads on a cell phone.

cheers, Gerhard

Hi, all of y'all, would you please snip the cited parts that are long out of context?!!one!eleven!!!!!! I wonder how that reads on a cell phone. cheers, Gerhard
PS
paul swed
Sat, Feb 13, 2021 4:17 PM

Several answers.
At temperature it can be adjusted to 5,000,000.0XX XX using just the coarse
adjustment. The Xs are because it has not really been on long enough to
seriously stabilize. Its been off/cold for easily bet 20-30 years.
The urq family of references were intended for shipboard use generally. As
mentioned in the 1970s the urq10 was in shirt sleeve environments on every
ship I was on and visited. Aircraft carriers to Oilers.
This unit has an extremely limited amount of information and as mentioned
this unit is absolutely some alpha version pre-release. I have guessed at
power supplies and Corby started all this with a URQ23 question. I started
looking at the urq23 manual and used that power supply design. +/- 15V 150
ma cold 30 40 ma hot.
OK back to this the 110 degrees seemed really too cool to me and thats
the question I asked. Was there such a thing as a crystal oven at 110
degrees.
There are to meter readings on the test meter. On FE units there is a
center red band. Assuming position 6 is outer oven its in the center red.
Position 7 assuming inner is at 9-11 off scale. When warming up it goes
through the center and you can actually see servo type behavior until its
off scale.
So that leads me to believe there is an issue. Granted nothing is labeled.
Just 1-9 on the switch.
The URQ13 could be a nice unit if working. Nothing like todays Rbs, Cs, and
GPSDOs. But you just never know when you will need a military class 1980s
reference. Chuckle. I always liked the URQ10s when I was in the service.
The ships all had 3 of them. But given they were all in exactly the same
location that seems like a poor consideration these days.
Regards
Paul
WB8TSL

On Sat, Feb 13, 2021 at 9:49 AM Bob kb8tq kb8tq@n1k.org wrote:

Hi

What frequency is it putting out?

Bob

On Feb 12, 2021, at 9:45 PM, paul swed paulswedb@gmail.com wrote:

I see a glass tape on the inner oven with writing "40.0". Thats it.
Assuming C its a long way off.The flask is fine the ovens are heating to
110F. Both of them. So somethings wrong. Interesting as I peel something
like caulking off the outer board I see what looks like a opamp. But its

a

FE house number. The top of the can has NSC. The old national

semiconductor

label. Could be a LM709 class opamp.

On Fri, Feb 12, 2021 at 9:12 PM Bob kb8tq kb8tq@n1k.org wrote:

Hi

If you are reading something below 60C on a dewar flask outer oven …. it
is borken….. very broken.

Bob

On Feb 12, 2021, at 7:25 PM, paul swed paulswedb@gmail.com wrote:

The temps I am reading are with a K thermocouple so pretty accurate. I

had

simply slid the thermocouple into the flask on the outer edge of the
ovens.The assembly is out of the flask now and both inner and outer are
heating. Will see what they do. Both seem to be heating at about the

same

rate. So the great news is the oven windings are not bad. I do see a

very

significant voltage difference on two leads that I might guess matter.

But

still decoding and reverse engineering everything.

On Fri, Feb 12, 2021 at 5:20 PM Bob kb8tq kb8tq@n1k.org wrote:

Hi

According to table 1-2 in:

http://www.navy-radio.com/freq/urq-eimb.pdf <
http://www.navy-radio.com/freq/urq-eimb.pdf>

The URQ-9 and URQ-10 both were rated for 0 to 50C.

Per:

http://www.navy-radio.com/freq/urq23-MIL-T-28816.pdf <
http://www.navy-radio.com/freq/urq23-MIL-T-28816.pdf>

The URQ-23 was rated for 0 to 50C

I’d say it’s a pretty likely that the URQ-13 was rated to operate over
0 to 50C. It went into the same locations and did the same thing as

the

other devices.

Bob

On Feb 12, 2021, at 1:07 PM, paul swed paulswedb@gmail.com wrote:

Well there is no doubt someone has been deep into this unit. Hint

missing

screws internally.
But appears both heater windings are ok.
So inner and outer oven has a new meaning. I typically understood

this

to

be one oven in another oven. Think the HP CS units of old. The same

in

other places HP3801.
But in the URQ13 it means there is a long tube. The Dewar flask. The

inner

is deep into the flask and the outer is close to the opening. Two
completely separate heaters. Under the outer heater I will guess is

the

actual oscillator for the 5 MHz. Further out from the outer heater

are

the

offset variable caps thermistor for the outer oven a pot and IC.
Several screws hold this outer heater on and considering the risk of

taking

out the remainders to look and draw a schematic.
Regards
Paul

On Fri, Feb 12, 2021 at 11:28 AM paul swed paulswedb@gmail.com

wrote:

Yes Bob they could get hot. But the radio rooms I have been in circa

1970s

were all air conditioned from destroyers to aircraft carriers. Shirt
sleeve. The best place to actually be when we were down by the

equator

was

the radio room, ET shop, CIC and radar and just maybe the Captain's
stateroom. But if you were actually there you might still be

sweating.

Chuckle.
This conversation has given me some good insights. Later today I

will

disable the outer oven. Just curious to see what possible temps

might

show

up. Is the inner oven simply reading outer oven leakage. Is there a

lead I

can measure the current of the inner oven....
Thanks

On Fri, Feb 12, 2021 at 11:18 AM Bob kb8tq kb8tq@n1k.org wrote:

Hi

If it’s 105F “outdoors” that’s 40C. Military gear back in the days

of

the

URQ10
did not live in air conditioned enclosures. It did get deployed to

places

with
temperatures at or above that level.

If it’s 40C outdoors, by the time you get to a pile of electronics

gear

indoors,
a >10C rise is pretty likely. That drives a very common 50C “upper

end”

temperature
on ground gear in relatively benign installations.

This does not just apply to military gear. If you look through test
equipment
catalogs, a lot of test gear also has the same sort of 50 to 60C

upper

end spec.
The 5065A has a spec of 0 to 50C. The 5061A has the same spec. Both
targeted
pretty “normal” environments …. ( = they never get below freezing

…)

and

date
to the “era” of the URQ10.

In this era of HVAC everywhere, the 5071A has a temp range of 0 to

55C.

If
anything, this would suggest that things still can get pretty hot.

Bob

On Feb 12, 2021, at 10:29 AM, paul swed paulswedb@gmail.com

wrote:

Bob
OK there is the math. and that all starts to line up.
So most likely for other URQ units there will be an ambient max in

the

spec's. At least on the URQ10 in real life even in the hot tropics

the

radio room was shirt sleeve temps.
But the question asked was 110 F correct as measured on the

outside

of

the

outer oven against the dewar flask correct. It isn't. The darn

thing

is

reasonably stable though.
Since the front panel test switch is not labeled I speculate that

the

position for the outer oven is in the normal range. The next

switch

position most likely is inner and is not in the correct position.

It

slowly

moves to the high side.
No real details on anything and a total guess.
Really appreciate the thoughts.
Regards
Paul
WB8TSL

On Fri, Feb 12, 2021 at 10:18 AM Bob kb8tq kb8tq@n1k.org wrote:

Hi

Indeed the outer oven (as a minimum) needs to be 5 to 10 C above
the maximum ambient. If it’s not it goes out of regulation (runs

away)

and you loose any benefit from it. ( = it now works against you

).

The inner oven as a minimum needs to be 5 to 10 C above the outer
oven. Again if it is lower, you can / will get into the same

runaway

issue.

Those offsets are dependent on the way things are insulated. If

you

are

using a dewar flask, 5C is probably not going to work for you.

Your inner oven also is impacted by the turn temperature on the

crystal

being used. This might have a 20C range. That would put the

maximum

inner oven temperature at 10 + 10 + 20 = 40C above the maximum

ambient.

Needless to say, if the max ambient is 85C, this will get the

inner

oven

components up pretty hot. That’s not a real good idea. Derating

the

heater

is pretty easy, derating everything in there is much more

complex.

You

do not often see 85C upper end double ovens ….

One could also ask: “is all this worth it?”. List members

have

written

papers addressing that point :)

Bob

On Feb 11, 2021, at 10:05 PM, Paul Alfille <

wrote:

Shouldn't the outer oven be cooler than the inner oven except

during

warmup? I would think the inner electronics would be generating

heat.

Paul Alfille K1PHA

On Thu, Feb 11, 2021 at 9:30 PM paul swed paulswedb@gmail.com

wrote:

50C is what I have sort of seen over the years. Just wondered

could

there

have been a lower temp version. That made no sense. But then

this

beast

has

never made a lot of sense. The $20 mystery from Frequency

Electronics.

Thanks Bob
Paul
WB8TSL

On Thu, Feb 11, 2021 at 8:08 PM Bob kb8tq kb8tq@n1k.org

wrote:

Hi

Even for an outer oven, anything below 60C / 140F would be low

enough

to

run into significant problems. On a mil device, an upper end

temperature

on
the equipment likely would be over 70C. The outer oven would

need

to be

5 to 10C above that.

Bob

On Feb 11, 2021, at 5:55 PM, paul swed paulswedb@gmail.com

wrote:

OK I have had several responses and 110F is low as I

expected.

Wonder if I am being faked out? Perhaps by an inner oven and

I

am

only

reading the outside of the outer oven. The Older URQ10 and

newer

URQ23

do

have 2 ovens. The meter switch for test is only labeled 1-9.

no

other

clues

to the function. I noticed 2 positions change with warm up.

Sort

of

supports the 2 oven theory.
Really do not want to take what might be the outer oven off

to

put

the

probe in.
Thanks everyone.
Paul
WB8TSL

On Thu, Feb 11, 2021 at 5:32 PM Bob kb8tq kb8tq@n1k.org

wrote:

Hi

110 F makes very little sense unless you are in a very cold

climate.

For military gear (or any gear for that matter) 43C on the

oven

just

doesn’t work.

110 C would make sense in a very high temperature

environment.

(think of 85C upper end ….).

Bob

On Feb 11, 2021, at 2:18 PM, paul swed <

wrote:

Hello to the group.
I have had a AN/URQ-13 or FE-15a oven oscillator for years.
Its never worked correctly and in reality some early alpha

build.

(Funny

that its labeled 15a)
Looking online there is no documentation that I have been

able

to

find

over

the years.
However in another discussion on a AN/URQ-23 that does

have a

manual

and

schematics I realized my guesses on power could be totally

wrong.

Using

voltages like the URQ23 the URQ13 actually behaves fairly

well. I

was

lucky

that I didn't destroy something with my original guess.
That said what I find odd is the internal crystal oven runs

at

exactly

110

degrees. Its repeatably warms to that level with a range of

supply

from

+/-

12-15V.
Does 110 degrees F make any sense at all?
Thank you
Paul
WB8TSL


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Several answers. At temperature it can be adjusted to 5,000,000.0XX XX using just the coarse adjustment. The Xs are because it has not really been on long enough to seriously stabilize. Its been off/cold for easily bet 20-30 years. The urq family of references were intended for shipboard use generally. As mentioned in the 1970s the urq10 was in shirt sleeve environments on every ship I was on and visited. Aircraft carriers to Oilers. This unit has an extremely limited amount of information and as mentioned this unit is absolutely some alpha version pre-release. I have guessed at power supplies and Corby started all this with a URQ23 question. I started looking at the urq23 manual and used that power supply design. +/- 15V 150 ma cold 30 40 ma hot. OK back to this the 110 degrees seemed really too cool to me and thats the question I asked. Was there such a thing as a crystal oven at 110 degrees. There are to meter readings on the test meter. On FE units there is a center red band. Assuming position 6 is outer oven its in the center red. Position 7 assuming inner is at 9-11 off scale. When warming up it goes through the center and you can actually see servo type behavior until its off scale. So that leads me to believe there is an issue. Granted nothing is labeled. Just 1-9 on the switch. The URQ13 could be a nice unit if working. Nothing like todays Rbs, Cs, and GPSDOs. But you just never know when you will need a military class 1980s reference. Chuckle. I always liked the URQ10s when I was in the service. The ships all had 3 of them. But given they were all in exactly the same location that seems like a poor consideration these days. Regards Paul WB8TSL On Sat, Feb 13, 2021 at 9:49 AM Bob kb8tq <kb8tq@n1k.org> wrote: > Hi > > What frequency is it putting out? > > Bob > > > On Feb 12, 2021, at 9:45 PM, paul swed <paulswedb@gmail.com> wrote: > > > > I see a glass tape on the inner oven with writing "40.0". Thats it. > > Assuming C its a long way off.The flask is fine the ovens are heating to > > 110F. Both of them. So somethings wrong. Interesting as I peel something > > like caulking off the outer board I see what looks like a opamp. But its > a > > FE house number. The top of the can has NSC. The old national > semiconductor > > label. Could be a LM709 class opamp. > > > > On Fri, Feb 12, 2021 at 9:12 PM Bob kb8tq <kb8tq@n1k.org> wrote: > > > >> Hi > >> > >> If you are reading something below 60C on a dewar flask outer oven …. it > >> is borken….. very broken. > >> > >> Bob > >> > >>> On Feb 12, 2021, at 7:25 PM, paul swed <paulswedb@gmail.com> wrote: > >>> > >>> The temps I am reading are with a K thermocouple so pretty accurate. I > >> had > >>> simply slid the thermocouple into the flask on the outer edge of the > >>> ovens.The assembly is out of the flask now and both inner and outer are > >>> heating. Will see what they do. Both seem to be heating at about the > same > >>> rate. So the great news is the oven windings are not bad. I do see a > very > >>> significant voltage difference on two leads that I might guess matter. > >> But > >>> still decoding and reverse engineering everything. > >>> > >>> On Fri, Feb 12, 2021 at 5:20 PM Bob kb8tq <kb8tq@n1k.org> wrote: > >>> > >>>> Hi > >>>> > >>>> According to table 1-2 in: > >>>> > >>>> http://www.navy-radio.com/freq/urq-eimb.pdf < > >>>> http://www.navy-radio.com/freq/urq-eimb.pdf> > >>>> > >>>> The URQ-9 and URQ-10 both were rated for 0 to 50C. > >>>> > >>>> Per: > >>>> > >>>> http://www.navy-radio.com/freq/urq23-MIL-T-28816.pdf < > >>>> http://www.navy-radio.com/freq/urq23-MIL-T-28816.pdf> > >>>> > >>>> The URQ-23 was rated for 0 to 50C > >>>> > >>>> I’d say it’s a pretty likely that the URQ-13 was rated to operate over > >>>> 0 to 50C. It went into the same locations and did the same thing as > the > >>>> other devices. > >>>> > >>>> Bob > >>>> > >>>> > >>>>> On Feb 12, 2021, at 1:07 PM, paul swed <paulswedb@gmail.com> wrote: > >>>>> > >>>>> Well there is no doubt someone has been deep into this unit. Hint > >> missing > >>>>> screws internally. > >>>>> But appears both heater windings are ok. > >>>>> So inner and outer oven has a new meaning. I typically understood > this > >> to > >>>>> be one oven in another oven. Think the HP CS units of old. The same > in > >>>>> other places HP3801. > >>>>> But in the URQ13 it means there is a long tube. The Dewar flask. The > >>>> inner > >>>>> is deep into the flask and the outer is close to the opening. Two > >>>>> completely separate heaters. Under the outer heater I will guess is > the > >>>>> actual oscillator for the 5 MHz. Further out from the outer heater > are > >>>> the > >>>>> offset variable caps thermistor for the outer oven a pot and IC. > >>>>> Several screws hold this outer heater on and considering the risk of > >>>> taking > >>>>> out the remainders to look and draw a schematic. > >>>>> Regards > >>>>> Paul > >>>>> > >>>>> On Fri, Feb 12, 2021 at 11:28 AM paul swed <paulswedb@gmail.com> > >> wrote: > >>>>> > >>>>>> Yes Bob they could get hot. But the radio rooms I have been in circa > >>>> 1970s > >>>>>> were all air conditioned from destroyers to aircraft carriers. Shirt > >>>>>> sleeve. The best place to actually be when we were down by the > equator > >>>> was > >>>>>> the radio room, ET shop, CIC and radar and just maybe the Captain's > >>>>>> stateroom. But if you were actually there you might still be > sweating. > >>>>>> Chuckle. > >>>>>> This conversation has given me some good insights. Later today I > will > >>>>>> disable the outer oven. Just curious to see what possible temps > might > >>>> show > >>>>>> up. Is the inner oven simply reading outer oven leakage. Is there a > >>>> lead I > >>>>>> can measure the current of the inner oven.... > >>>>>> Thanks > >>>>>> > >>>>>> On Fri, Feb 12, 2021 at 11:18 AM Bob kb8tq <kb8tq@n1k.org> wrote: > >>>>>> > >>>>>>> Hi > >>>>>>> > >>>>>>> If it’s 105F “outdoors” that’s 40C. Military gear back in the days > of > >>>> the > >>>>>>> URQ10 > >>>>>>> did not live in air conditioned enclosures. It did get deployed to > >>>> places > >>>>>>> with > >>>>>>> temperatures at or above that level. > >>>>>>> > >>>>>>> If it’s 40C outdoors, by the time you get to a pile of electronics > >> gear > >>>>>>> *indoors*, > >>>>>>> a >10C rise is pretty likely. That drives a very common 50C “upper > >> end” > >>>>>>> temperature > >>>>>>> on ground gear in relatively benign installations. > >>>>>>> > >>>>>>> This does not just apply to military gear. If you look through test > >>>>>>> equipment > >>>>>>> catalogs, a lot of test gear also has the same sort of 50 to 60C > >> upper > >>>>>>> end spec. > >>>>>>> The 5065A has a spec of 0 to 50C. The 5061A has the same spec. Both > >>>>>>> targeted > >>>>>>> pretty “normal” environments …. ( = they never get below freezing > …) > >>>> and > >>>>>>> date > >>>>>>> to the “era” of the URQ10. > >>>>>>> > >>>>>>> In this era of HVAC everywhere, the 5071A has a temp range of 0 to > >> 55C. > >>>>>>> If > >>>>>>> anything, this would suggest that things still can get pretty hot. > >>>>>>> > >>>>>>> Bob > >>>>>>> > >>>>>>>> On Feb 12, 2021, at 10:29 AM, paul swed <paulswedb@gmail.com> > >> wrote: > >>>>>>>> > >>>>>>>> Bob > >>>>>>>> OK there is the math. and that all starts to line up. > >>>>>>>> So most likely for other URQ units there will be an ambient max in > >> the > >>>>>>>> spec's. At least on the URQ10 in real life even in the hot tropics > >> the > >>>>>>>> radio room was shirt sleeve temps. > >>>>>>>> But the question asked was 110 F correct as measured on the > outside > >> of > >>>>>>> the > >>>>>>>> outer oven against the dewar flask correct. It isn't. The darn > thing > >>>> is > >>>>>>>> reasonably stable though. > >>>>>>>> Since the front panel test switch is not labeled I speculate that > >> the > >>>>>>>> position for the outer oven is in the normal range. The next > switch > >>>>>>>> position most likely is inner and is not in the correct position. > It > >>>>>>> slowly > >>>>>>>> moves to the high side. > >>>>>>>> No real details on anything and a total guess. > >>>>>>>> Really appreciate the thoughts. > >>>>>>>> Regards > >>>>>>>> Paul > >>>>>>>> WB8TSL > >>>>>>>> > >>>>>>>> On Fri, Feb 12, 2021 at 10:18 AM Bob kb8tq <kb8tq@n1k.org> wrote: > >>>>>>>> > >>>>>>>>> Hi > >>>>>>>>> > >>>>>>>>> Indeed the outer oven (as a minimum) needs to be 5 to 10 C above > >>>>>>>>> the maximum ambient. If it’s not it goes out of regulation (runs > >>>> away) > >>>>>>>>> and you loose any benefit from it. ( = it now works against you > ). > >>>>>>>>> > >>>>>>>>> The inner oven as a minimum needs to be 5 to 10 C above the outer > >>>>>>>>> oven. Again if it is lower, you can / will get into the same > >> runaway > >>>>>>>>> issue. > >>>>>>>>> > >>>>>>>>> Those offsets are dependent on the way things are insulated. If > you > >>>> are > >>>>>>>>> using a dewar flask, 5C is probably not going to work for you. > >>>>>>>>> > >>>>>>>>> Your inner oven *also* is impacted by the turn temperature on the > >>>>>>> crystal > >>>>>>>>> being used. This *might* have a 20C range. That would put the > >> maximum > >>>>>>>>> inner oven temperature at 10 + 10 + 20 = 40C above the maximum > >>>> ambient. > >>>>>>>>> > >>>>>>>>> Needless to say, if the max ambient is 85C, this will get the > inner > >>>>>>> oven > >>>>>>>>> components up pretty hot. That’s not a real good idea. Derating > the > >>>>>>> heater > >>>>>>>>> is pretty easy, derating *everything* in there is much more > >> complex. > >>>>>>> You > >>>>>>>>> do not often see 85C upper end double ovens …. > >>>>>>>>> > >>>>>>>>> One *could* also ask: “is all this worth it?”. List members > *have* > >>>>>>> written > >>>>>>>>> papers addressing that point :) > >>>>>>>>> > >>>>>>>>> Bob > >>>>>>>>> > >>>>>>>>>> On Feb 11, 2021, at 10:05 PM, Paul Alfille < > >> paul.alfille@gmail.com> > >>>>>>>>> wrote: > >>>>>>>>>> > >>>>>>>>>> Shouldn't the outer oven be cooler than the inner oven except > >> during > >>>>>>>>>> warmup? I would think the inner electronics would be generating > >>>> heat. > >>>>>>>>>> > >>>>>>>>>> Paul Alfille K1PHA > >>>>>>>>>> > >>>>>>>>>> On Thu, Feb 11, 2021 at 9:30 PM paul swed <paulswedb@gmail.com> > >>>>>>> wrote: > >>>>>>>>>> > >>>>>>>>>>> 50C is what I have sort of seen over the years. Just wondered > >> could > >>>>>>>>> there > >>>>>>>>>>> have been a lower temp version. That made no sense. But then > this > >>>>>>> beast > >>>>>>>>> has > >>>>>>>>>>> never made a lot of sense. The $20 mystery from Frequency > >>>>>>> Electronics. > >>>>>>>>>>> Thanks Bob > >>>>>>>>>>> Paul > >>>>>>>>>>> WB8TSL > >>>>>>>>>>> > >>>>>>>>>>> On Thu, Feb 11, 2021 at 8:08 PM Bob kb8tq <kb8tq@n1k.org> > wrote: > >>>>>>>>>>> > >>>>>>>>>>>> Hi > >>>>>>>>>>>> > >>>>>>>>>>>> Even for an outer oven, anything below 60C / 140F would be low > >>>>>>> enough > >>>>>>>>> to > >>>>>>>>>>>> run into significant problems. On a mil device, an upper end > >>>>>>>>> temperature > >>>>>>>>>>>> on > >>>>>>>>>>>> the equipment likely would be over 70C. The outer oven would > >> need > >>>>>>> to be > >>>>>>>>>>>> 5 to 10C above that. > >>>>>>>>>>>> > >>>>>>>>>>>> Bob > >>>>>>>>>>>> > >>>>>>>>>>>>> On Feb 11, 2021, at 5:55 PM, paul swed <paulswedb@gmail.com> > >>>>>>> wrote: > >>>>>>>>>>>>> > >>>>>>>>>>>>> OK I have had several responses and 110F is low as I > expected. > >>>>>>>>>>>>> Wonder if I am being faked out? Perhaps by an inner oven and > I > >> am > >>>>>>> only > >>>>>>>>>>>>> reading the outside of the outer oven. The Older URQ10 and > >> newer > >>>>>>> URQ23 > >>>>>>>>>>> do > >>>>>>>>>>>>> have 2 ovens. The meter switch for test is only labeled 1-9. > no > >>>>>>> other > >>>>>>>>>>>> clues > >>>>>>>>>>>>> to the function. I noticed 2 positions change with warm up. > >> Sort > >>>> of > >>>>>>>>>>>>> supports the 2 oven theory. > >>>>>>>>>>>>> Really do not want to take what might be the outer oven off > to > >>>> put > >>>>>>> the > >>>>>>>>>>>>> probe in. > >>>>>>>>>>>>> Thanks everyone. > >>>>>>>>>>>>> Paul > >>>>>>>>>>>>> WB8TSL > >>>>>>>>>>>>> > >>>>>>>>>>>>> On Thu, Feb 11, 2021 at 5:32 PM Bob kb8tq <kb8tq@n1k.org> > >> wrote: > >>>>>>>>>>>>> > >>>>>>>>>>>>>> Hi > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> 110 F makes very little sense unless you are in a very cold > >>>>>>> climate. > >>>>>>>>>>>>>> For military gear (or any gear for that matter) 43C on the > >> oven > >>>>>>> just > >>>>>>>>>>>>>> doesn’t work. > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> 110 C would make sense in a very high temperature > environment. > >>>>>>>>>>>>>> (think of 85C upper end ….). > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> Bob > >>>>>>>>>>>>>> > >>>>>>>>>>>>>>> On Feb 11, 2021, at 2:18 PM, paul swed < > paulswedb@gmail.com> > >>>>>>> wrote: > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> Hello to the group. > >>>>>>>>>>>>>>> I have had a AN/URQ-13 or FE-15a oven oscillator for years. > >>>>>>>>>>>>>>> Its never worked correctly and in reality some early alpha > >>>> build. > >>>>>>>>>>>> (Funny > >>>>>>>>>>>>>>> that its labeled 15a) > >>>>>>>>>>>>>>> Looking online there is no documentation that I have been > >> able > >>>> to > >>>>>>>>>>> find > >>>>>>>>>>>>>> over > >>>>>>>>>>>>>>> the years. > >>>>>>>>>>>>>>> However in another discussion on a AN/URQ-23 that does > have a > >>>>>>> manual > >>>>>>>>>>>> and > >>>>>>>>>>>>>>> schematics I realized my guesses on power could be totally > >>>> wrong. > >>>>>>>>>>> Using > >>>>>>>>>>>>>>> voltages like the URQ23 the URQ13 actually behaves fairly > >>>> well. I > >>>>>>>>> was > >>>>>>>>>>>>>> lucky > >>>>>>>>>>>>>>> that I didn't destroy something with my original guess. > >>>>>>>>>>>>>>> That said what I find odd is the internal crystal oven runs > >> at > >>>>>>>>>>> exactly > >>>>>>>>>>>>>> 110 > >>>>>>>>>>>>>>> degrees. Its repeatably warms to that level with a range of > >>>>>>> supply > >>>>>>>>>>> from > >>>>>>>>>>>>>> +/- > >>>>>>>>>>>>>>> 12-15V. > >>>>>>>>>>>>>>> Does 110 degrees F make any sense at all? > >>>>>>>>>>>>>>> Thank you > >>>>>>>>>>>>>>> Paul > >>>>>>>>>>>>>>> WB8TSL > >>>>>>>>>>>>>>> _______________________________________________ > >>>>>>>>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com > >>>>>>>>>>>>>>> To unsubscribe, go to > >>>>>>>>>>>>>> > >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>>>>>>>>>>>>>> and follow the instructions there. > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> _______________________________________________ > >>>>>>>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com > >>>>>>>>>>>>>> To unsubscribe, go to > >>>>>>>>>>>>>> > >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>>>>>>>>>>>>> and follow the instructions there. > >>>>>>>>>>>>>> > >>>>>>>>>>>>> _______________________________________________ > >>>>>>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com > >>>>>>>>>>>>> To unsubscribe, go to > >>>>>>>>>>>> > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>>>>>>>>>>>> and follow the instructions there. > >>>>>>>>>>>> > >>>>>>>>>>>> > >>>>>>>>>>>> _______________________________________________ > >>>>>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com > >>>>>>>>>>>> To unsubscribe, go to > >>>>>>>>>>>> > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>>>>>>>>>>> and follow the instructions there. > >>>>>>>>>>>> > >>>>>>>>>>> _______________________________________________ > >>>>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com > >>>>>>>>>>> To unsubscribe, go to > >>>>>>>>>>> > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>>>>>>>>>> and follow the instructions there. > >>>>>>>>>>> > >>>>>>>>>> _______________________________________________ > >>>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com > >>>>>>>>>> To unsubscribe, go to > >>>>>>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>>>>>>>>> and follow the instructions there. > >>>>>>>>> > >>>>>>>>> > >>>>>>>>> _______________________________________________ > >>>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com > >>>>>>>>> To unsubscribe, go to > >>>>>>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>>>>>>>> and follow the instructions there. > >>>>>>>>> > >>>>>>>> _______________________________________________ > >>>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com > >>>>>>>> To unsubscribe, go to > >>>>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>>>>>>> and follow the instructions there. > >>>>>>> > >>>>>>> > >>>>>>> _______________________________________________ > >>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com > >>>>>>> To unsubscribe, go to > >>>>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>>>>>> and follow the instructions there. > >>>>>>> > >>>>>> > >>>>> _______________________________________________ > >>>>> time-nuts mailing list -- time-nuts@lists.febo.com > >>>>> To unsubscribe, go to > >>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>>>> and follow the instructions there. > >>>> > >>>> _______________________________________________ > >>>> time-nuts mailing list -- time-nuts@lists.febo.com > >>>> To unsubscribe, go to > >>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>>> and follow the instructions there. > >>>> > >>> _______________________________________________ > >>> time-nuts mailing list -- time-nuts@lists.febo.com > >>> To unsubscribe, go to > >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>> and follow the instructions there. > >> > >> > >> _______________________________________________ > >> time-nuts mailing list -- time-nuts@lists.febo.com > >> To unsubscribe, go to > >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >> and follow the instructions there. > >> > > _______________________________________________ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. >