> > I probably could discipline the internal 5 MHz to an external GPS > > > Lester B Veenstra K1YCM MØYCM W8YCM 6Y6Y > > lester@veenstras.com > >************************** I have a 5061A here that has been running for years with a Brooks Shera GPS disciplining system built into the battery compartment. I have arranged it so that the Cs can still be used as the Cs tube was still OK last time I had it on but clearly it's getting pretty old now. One thing I have found with these devices is that the ion pump power unit is prone to fail. I have repaired one or two - usually the 100M resistor in there is the problem. I'm down here in Australia where replacements are hard to find so if anyone is parting out a unit with a worn out tube I'd appreciate a chance to obtain the ion pump supply module. 73, Morris Odell VK3DOC Melbourne, Australia >