The AM Forum

Anyone else have one of these?
It seems I have two now.
Niether one works 8-(
It's apparently more than just a receiver. besides the scope, it apparently has filters for the different signals sent by WWV and means of comparing the received signals to a local signal or standard.

This one has apparently has had a Collins F455J31 mechanical filter substituted (for what??) and has AN type connectors put on the back. I'm going to order the manual if I can find it. No joy last time.

WWV receiver
Model WWVC
Nr. 435
Specific Products
LA, CA

Patrick,

Those look suspicious. Dangerous. Probably has HIGH VOLTAGE inside!!
NO USER SERVICEABLE PARTS.

May Contain Lead!!!

What's more, and certainly, materials and substances known to cause cancer in the State of
California!!

I'd like to help you... dispose of this hazardous material!!
Just let me know?
I'm here, qualified to deal with such things.

                _-_-bear

The other one.. And the Pr0n of it.  took a while to find the files from 2011.

High Voltage? I better not mess with it. I'll have one of my minions do it!

I couldn't resist some mischief.
The  one with the white-faced CRT is working, that is, it makes noise and the BFO works, but I don't have an antenna in the house at the moment, so I was just picking up the household noises.

Couple things on it -
It's 115V, and on 125V the voltages are a little high.

The 6AK6 audio output tube is running real hot with 245V on the plate and -2V bias on the grid. The tube manual says 180V with a -9V grid bias.

The negative bias seems to come from the CRT's cathode voltage supply bleeder string via 6X4. So it needs gone through, recapped in the power supplies and the high value resistors checked in the CRT circuit because they often go bad in those kind of circuits.

I don't know why someone removed the 455KC plug-in collins mechanical filter and bypassed it with a 1K resistor and a 1000pF load, but I want to find one for it later after I determine it's going to work.

I'd love to find a manual, or just a schematic. I've run some bench tests and the performance is excellent on some bands. Mine needs a good alignment, but even out-of-spec, it performs quite well.

Looks as if it may have been used for working with one of the old Simplex master clock systems providing a reference? with direct access to the internal scope maybe it can also be used as a method of calibrating different signals with WWV?
With all the other weird stuff you have got to ask if you got a Rubidium Standard and you can beat that with that receiver and try to approach accuracy close to GPS?

Good question. The instrument will precisely compare a Rubidium standard to the WWV signal. There will be jitter or whatever one wants to call it coming from the over-the-air path. It's for comparing your frequency standard, whatever it may be, to WWV.

Manual for the Specific Products WWVC attached

You, sir, are a gentleman and a saint!