[R-390] The second 390A

[dog]

OK, I've got an old HP410B that I can drag out of the back of the shop. 
I did something to fix it last year. I think the diode tube is still 
good in it too. I've also got a Boonton RF mVmeter, but it's really got 
a Moto label on it I think it's got about a 2pf load. Between all that I 
should be able to detect something. As I remember I just used to wrap a 
wire around V401 and feed it into the spectrum analyzer. But I do notice 
I'm not getting noise difference rotating the ant trim on #2, so 
something's not working right in the RF section somewhere. The IF works 
just like the other one at the input of J513 so I think the IF and audio 
sections are OK. I need to measure the B+ at some point though, I 
haven't done that yet. I've just been sorta letting it warm up and 
keeping an eye on it while I'm in the shop.

On 7/17/2019 22:23, dog wrote:
> I got the second RX put back together today, new meters, all the stuff 
> soldered back in place, all the modules installed, new re-wired PS 
> with the tubes, turn it on and it plays, noise from the headphone 
> jack, BW, BFO, Meters, etc seem to work. Check the osc voltages and 
> E209 is -9.4VDC, E210 is -2.2VDC, E211 is -2.65VDC, (not too bad) but 
> E402 is 0. Test the #1 390A which is working and the E402 is also 
> 0VDC. What is going on here? I haven't put RF into the newly fixed 
> input yet.
>
> I also need one of those BNC to mini BNC adapters (J116) for the IF 
> module. Stole it out of the other RX for now to test stuff. I don't 
> think I every got a DC voltage reading on E402 in the past, I'm 
> wondering what that is about, especially when the fixed RX works?
>
> Got a lot done today getting the old one back together without too 
> much missing.
>
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