[Elecraft] 10 MHz Reference Oscillator

[Bob W7AVK]

For evaluation I purchased last spring directly from China one of the 
BG7TBL 10 mhz sine output GPS Defined Oscillators when the price was 
$125.  These very nice units are now being sold from CA for a bit more 
and comes with everything needed, Unit, GPS antenna, power supply. 
http://www.ebay.com/itm/10MHZ-Output-Sine-Wave-GPS-Disciplined-Clock-GPSDO-GPS-Antenna-Power-Supply-US-/261977676713?hash=item3cff161ba9:g:ZJQAAOSwrklVf3wV 


It uses the Russian Morion Double oven crystal oscillators controlled by 
voltage feedback against the  GPS1 pulse per second signal using a very 
long time constant control loop.  If you would like a block drawing 
contact me directly.

I gave the unit to KE5FX, a member of the "Time Nuts" group, who has the 
equipment to evaluate it.  His results are posted at 
http://www.ke5fx.com/gpscomp.htm It was found due to the pulse width 
method of creating the Morion oscillator control voltage this unit was 
operating 2 to 3 times ten to the minus 11 cycles low.   I wouldn't get 
too upset at this as that error would only be 3 hz off at 100 GHZ.

Found the unit works great as a master reference for not only the K3 but 
lab gear like counters and signal generators.

73  Bob  W7AVK