The only "problems" connected to the R-390/URR are the 47 Ohm resistors under
the chassis, four of them if my memory is right.
They are usually slightly charred from heat...
There is a solid state kit available that reduces the heat from the PS. Google
it.
No problem caps. Remember this
wasn't a cost reduced receiver like the R-390A.
Les
----- Original Message -----
From: Adam Morehouse <[email protected]>
To: Les Locklear <[email protected]>
Cc: R390 qth list <[email protected]>
Sent: 10/4/2025 6:59:08 PM
Subject: Re: [R-390] R-392
All back to stock, and still working. Dial accuracy is a lot better, and I'm
pulling in all sorts of stuff on 40m with a magnetic loop in my basement.
It's good enough.
Now onto the R-390 this week (and beyond). It has issues, very low distorted audio. I haven't
done much besides plug it in and bring it up slowly to test it out.
Are there any caps/resistors in an R-390 that should be replaced off the bat?
It seems weird without electrolytics like the R390A.
On Sat, Oct 4, 2025 at 6:24 PM Les Locklear <[email protected]> wrote:
That's great! Who knows what the gremlin was, the main thing is it's working!
Les
----- Original Message -----
From: Adam Morehouse <[email protected]>
To: Les Locklear <[email protected]>
Cc: R390 qth list <[email protected]>
Sent: 10/4/2025 5:14:36 PM
Subject: Re: [R-390] R-392
Les,
I just took the PTO out and apart, nothing was apparently wrong, but I reflowed
the connections for the 2 caps. Before I put the bottom decks back in, I
noticed a connection between the bottom of the RF and the crystal
calibrator...like a button that makes contact between them when put together.
It was pretty smooshed and not making contact. I fixed that, and after putting
it all together...it works.
Loud and clear, the dial is about 25kc off. I might stick the original RF deck
back in and see if
it's closer and still working, then do an alignment (my first on a R39x...)
What a strange issue but im glad it's
fixed. Whatever it was...
Adam
On Sat, Oct 4, 2025, 17:22 Les Locklear <[email protected]> wrote:
Open the PTO
don't be scared of it. You will probably find two small temp compensating caps, 10 pf if my memory is working. They have a tendency to
spring away from their solder connection maybe from a drop or whatever. Reflow
the joint and test. I found that problem with a 1962 Amelco R-390A PTO.
Les Locklear
----- Original Message -----
From: Adam Morehouse <[email protected]>
To: Jacques Fortin <[email protected]>
Cc: R-390 Mailing List <[email protected]>
Sent: 10/4/2025 3:14:56 PM
Subject: Re: [R-390] R-392
________________________________________________________________________________
Alright, so the oscillator is working. I think my problem has to do with
the PTO.
When I bought the T-195/GRC-19 it came with a tote of parts - I swapped the
AF/IF/Crystal Calibrator decks out - made no difference. Then I swapped RF
decks - no difference.
I noticed the wiring harness for the big plug on the AF deck had some
electrical tape, I unwrapped it and don't
see any damaged wires, switches
behind the front plate look clean, with no loose or broken wires.
But it still makes noises when I gently tap around. I left it tuned to a
nearby AM station and flipped the unit over, and it (kinda) came to life.
Squealing, and awful sounding - tapping around with a screwdriver,
primarily on the PTO seems to affect it the most.
Anyone have experience with that?
Here's a video....
https://photos.app.goo.gl/AZga9HyCqnJ1hyo18
On Fri, Oct 3, 2025 at 9:29 AM Jacques Fortin <[email protected]>
wrote:
Hello Adam,
Swapping the tubes is a good idea, but that do not insure that the 1st
Xtal oscillator is actually working...
You should try to measure if there is any signal on the V401 plate.
This being said, I do not own a R-392, but it is similar to a R-390/URR in
architecture.
Do you have a copy of the TM11-858 or the TM11-5820-334-35 ??
73, Jacques, VE2JFE in Montreal
-----Message d'origine-----
De : [email protected] <[email protected]> De la
part de Adam Morehouse
Envoyé : 2 octobre 2025 13:59
À : R-390 Mailing List <[email protected]>
Objet : Re: [R-390] R-392
Managed to get the V401/V203 tubes out with a little bit of gorilla tape
as a puller. The silicone puller I bought just slips right off them...
I swapped tubes, no changes. The switch seems to be working fine, when I
first start playing with this thing, if I tapped the chassis it would click
in the speaker, like a bad connection, etc. I took the bottom decks out,
and dropped the front panel and saw nothing obvious poking around. Now that
it's back together, its gone.
A lot of the tubes do test "low" on my Heathkit TT-1 tube tester (TV-7 in
the pile of stuff to restore/calibrate).
V401
1. -.3 / 118k
2. .01 / 8.4
3. 5.8 / 6.2
4. 11.38 / 10.3
5. 21.9 / 1k
6. 21.9 / 1k
7. .013 / 8.4
V203
1. 0 / 107k
2. 0 / 3.5k
3. 0 / .3
4. 23.99 / 3.7
5. 10.5v / 8.8M
6. .17 / OL
7. 23.15 / 2k
On Wed, Oct 1, 2025 at 8:08 PM Adam Morehouse <[email protected]>
wrote:
Hey guys,
Doing a little tinkering between classes (18 credits is awful...). I
decided to try out a R-392 that came with a T-195 I bought this summer.
It's
nice and clean inside, no obvious defects - but is completely
dead below 8MHz. Any idea where I should start my search when I dig into
this?
Thanks for any help or pointers...
Adam
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Please help support this email list: http://www.qsl.net/donate.html
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