Empathy List Archives

BG

Bruce Griffiths

Sat, Feb 12, 2011 10:12 PM

Kevin Rosenberg wrote:

On Feb 11, 2011, at 9:44 PM, Neville Michie wrote:

[...]For the minus 12v I used a ICL7662, these are rare, so a cmos gate oscillator and diode pump negative generator could be used. I am told the -12V is quite uncritical.[...]

Thanks for the thoughts. I'm thinking about redoing the power supplies for my T-bolts.
So, your comments are helpful.

May I ask where is the ICL7662 rare? Digikey has over 20K in various forms.

I've also heard that the 5V supply is not noise critical. For your minimum power goal,
I imagine that's why you used a switcher rather than lose up to 0.4A x 7V (2.8W) using
a linear 5V regular off the +12V line.

Kevin

You could look at using a variant of the Cuk switching regulator.
These can have relatively low input and output noise before any
additional filters that may be added.

Bruce

Kevin Rosenberg wrote: > On Feb 11, 2011, at 9:44 PM, Neville Michie wrote: > >> [...]For the minus 12v I used a ICL7662, these are rare, so a cmos gate oscillator and diode pump negative generator could be used. I am told the -12V is quite uncritical.[...] >> > Thanks for the thoughts. I'm thinking about redoing the power supplies for my T-bolts. > So, your comments are helpful. > > May I ask where is the ICL7662 rare? Digikey has over 20K in various forms. > > I've also heard that the 5V supply is not noise critical. For your minimum power goal, > I imagine that's why you used a switcher rather than lose up to 0.4A x 7V (2.8W) using > a linear 5V regular off the +12V line. > > Kevin > > > You could look at using a variant of the Cuk switching regulator. These can have relatively low input and output noise before any additional filters that may be added. Bruce

MJ

Mark J. Blair

Sun, Feb 13, 2011 3:16 AM

On Feb 10, 2011, at 3:16 PM, Larry McDavid wrote:

I'm seeking a recommendation for a power supply for this Thunderbolt receiver.

I use an HP 6236B that I bought inexpensively on eBay, after reading about others having good results with that combination. I had to repair it (it had one or two bad caps), but it was still inexpensive after the cost of the components. The TBolt draws more than the supply's rated current on the +12V output during cold start, but neither the TBolt nor the power supply seem to mind, and the operating current settles down into the supply's normal operating range after a few minutes of warm-up.

I have the TBolt bolted right on top of the supply (over the coolest corner). This is far from ideal, but the supply's ventilation holes are conveniently spaced to line up with the T-Bolt's mounting holes. I'll improve my setup eventually, when I feel a surge of time-nuttiness coming on. :) Even in its current configuration, it far exceeds my needs for a frequency reference.

--
Mark J. Blair, NF6X nf6x@nf6x.net
Web page: http://www.nf6x.net/
GnuPG public key available from my web page.

On Feb 10, 2011, at 3:16 PM, Larry McDavid wrote: > I'm seeking a recommendation for a power supply for this Thunderbolt receiver. I use an HP 6236B that I bought inexpensively on eBay, after reading about others having good results with that combination. I had to repair it (it had one or two bad caps), but it was still inexpensive after the cost of the components. The TBolt draws more than the supply's rated current on the +12V output during cold start, but neither the TBolt nor the power supply seem to mind, and the operating current settles down into the supply's normal operating range after a few minutes of warm-up. I have the TBolt bolted right on top of the supply (over the coolest corner). This is far from ideal, but the supply's ventilation holes are conveniently spaced to line up with the T-Bolt's mounting holes. I'll improve my setup eventually, when I feel a surge of time-nuttiness coming on. :) Even in its current configuration, it far exceeds my needs for a frequency reference. -- Mark J. Blair, NF6X <nf6x@nf6x.net> Web page: http://www.nf6x.net/ GnuPG public key available from my web page.

KR

Kevin Rosenberg

Sun, Feb 13, 2011 7:00 AM

On Feb 12, 2011, at 3:12 PM, Bruce Griffiths wrote:

Cuk switching regulator

Thanks for the tip!

Kevin

On Feb 12, 2011, at 3:12 PM, Bruce Griffiths wrote: > Cuk switching regulator Thanks for the tip! Kevin

KR

Kevin Rosenberg

Sun, Feb 13, 2011 7:03 AM

On Feb 12, 2011, at 8:16 PM, Mark J. Blair wrote:

my setup eventually, when I feel a surge of time-nuttiness coming on. :) Even in its current configuration, it far exceeds my needs for a frequency reference.

Exceeding your needs? Doesn't seen like that surge of time-nuttiness has hit yet ;)

Kevin

On Feb 12, 2011, at 8:16 PM, Mark J. Blair wrote: > my setup eventually, when I feel a surge of time-nuttiness coming on. :) Even in its current configuration, it far exceeds my needs for a frequency reference. Exceeding your needs? Doesn't seen like that surge of time-nuttiness has hit yet ;) Kevin

MJ

Mark J. Blair

Sun, Feb 13, 2011 7:53 AM

On Feb 12, 2011, at 11:03 PM, Kevin Rosenberg wrote:

Exceeding your needs? Doesn't seen like that surge of time-nuttiness has hit yet ;)

Don't worry, I'm just pacing myself. :)

--
Mark J. Blair, NF6X nf6x@nf6x.net
Web page: http://www.nf6x.net/
GnuPG public key available from my web page.

On Feb 12, 2011, at 11:03 PM, Kevin Rosenberg wrote: > Exceeding your needs? Doesn't seen like that surge of time-nuttiness has hit yet ;) Don't worry, I'm just pacing myself. :) -- Mark J. Blair, NF6X <nf6x@nf6x.net> Web page: http://www.nf6x.net/ GnuPG public key available from my web page.

time-nuts@lists.febo.com

Thunderbolt Supply