Hi,
So I'm trying to advance my station to something useful and last night I
waded into some issues with my Ten Tec RX-325 receiver. I don't have
good information about aligning the PLL section but I do have some
documents from Ten Tec regarding the RX-325 and a similar RX they built
for the Navy, the SP-325. I was able to identify the principle clock
oscillator adjustment and using my counter and WWV for reality checks I
got that living where it needs to be. There is another xtal oscillator
that is required to be on the correct frequency and no good way to
measure it's frequency directly at my shack. The levels I was able to
pick off did not give me a stable readout on my counter. WWV and some
broadcast stations to the rescue. If either oscillator is off - the RX
won't track. Well it does now. The BFO at 455 kc has two adjustments and
I worked out which one is related to what sideband and what order they
must be used - they're interactive! That RX is working nicely now. The
SSB filter seems to be adequate so I scrapped plans to install the
collins filter - for now.
Along the way I discovered a cold solder joint on the IF board and
removed/repaired/reinstalled that. When you remove the bottom cover on
the RX-325 you have to be careful not to break the wires on the speaker
- go ahead and ask me how I know this. I repaired that, too. I put some
strain relief on the lil short speaker leads while I was at it. Finally,
I dialed some signals in the ham bands to see how it was doing. There
was a horrible racket on 160 meters! One of my shop lights is dying.
I'll identify the particular curly looking bulb tomorrow and replace it.
The 325 is doing a pretty good job. I made a lot of progress with my
station. I am going to add an audio filter ala the old Argonaut 509 to
improve the signal sorting but I am not having much trouble sorting the
signals with my gray filter as-is - even with the contest weekend.
Tomorrow is a free day and I am going to try to get the feedline for a
new (real) antenna routed from in here to out there. Then get wire up in
the trees as high as I can. If that goes as well as the TLC job on the
325 I'll be doing great.
Next - TLC for the transmitter.
73,
Bill KU8H
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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