Using the R-390 with my Viking II in Break in mode.

[N6YW]

Greetings to all
I finally made the grade and produced plate modulated AM for the very first time!
The Viking II lives and apparently, many good reports on the AMI net on 3870 Wednesday night.
I was using my SP-600 and haven't yet figured out how to mute it when transmitting, so I did it manually.
What a pain, so today I am attempting my first QSO's on 10 meter AM using my R-390.
How does break in work with the 390? I am using a Dow Key Relay with the Viking II and have access to the two sets of external relay contacts, N/C and N/O.
Thanks in advance.
Billy N6YW

[Todd, KA1KAQ]

Something I'll be doing in the future with an A model. As it was explained to me by Joe/WA2PJP during his recent visit, simply utilize the built in antenna relay. Use the Break In and GND connections on the rear apron, then switch to break in on the front panel.

As well, you can use a set of normally-close contacts on the Dow Key to break the RF gain line on the back, pointed out to me by Johnny W3JN.

One keeps you from dumping RF into the receiver, the other mutes the audio, or something like that.  

I'm sure Johnny or others will jump in if I've got it wrong here, having not yet done it myself.

As far as the SP-600, the one I just picked up from Steve K4HX has an extra cable attached to the Send/Standby switch then running out the back. I suspect this was to close the circuit externally to bypass the need for manual switching. That's another one I haven't used beyond stand alone receiving.

[WD8KDG]

On the R390/A use the break in contacts on the rear apron, turn the front panel break-in switch to ON. I tried the additional method of opening the RF gain contacts on the rear apron and believe doing so caused some problems. The RF gain pot on the front panel tends to burn a spot on the resistance substrate in the pot.

So, I'm back to just using the break-in contact and ground on the rear apron. YMMV.

Craig,

[N6YW]

I tried the break in method using the barrier strip terminals on the back. It does nothing. The RF gain/relay contact method does work though. Now that you mention a possible problem to the RF gain pot being caused I am now skeptical. Does anyone have any idea why the break in method doesn't work on my 390?
This is a non-A model, early serial number #1023

[WA3VJB]

Billy congratulations on getting on the air with the Johnson, the Hammarlund and the Collins (I guess it could be a Motorola R390). You keep good company !

First -- make sure the Break In switch is on !!!  (hey, ya never know)

I would check the break in relay itself, and while you''re in there check the squelch relay.  Both shunt the audio when activated. If neither is working then it could be a cable connector that needs to be re-seated. While you're in there you can verify the supply voltage.


Presume you've got documentation, but if not ---

http://bama.edebris.com/manuals/military/r390/

[N6YW]

Billy congratulations on getting on the air with the Johnson, the Hammarlund and the Collins (I guess it could be a Motorola R390). You keep good company !

First -- make sure the Break In switch is on !!!  (hey, ya never know)

I would check the break in relay itself, and while you''re in there check the squelch relay.  Both shunt the audio when activated. If neither is working then it could be a cable connector that needs to be re-seated. While you're in there you can verify the supply voltage.


Presume you've got documentation, but if not ---

Okay, I will do that!
The 390 is a Collins and was stored in a container building, outside of Carson City Nevada for a number of years.  It's a bit dirty but the darn thing fired right up after a good ramp up on the variac. And, thank you for posting the Bama document. No, I have not acquired a shop manual for the 390 yet. There is a guy on Ebay that sells some pretty nice laser print copies with fold outs for a reasonable cost.
Anyway, it is likely that the relays are filthy. Maybe it's time for a trip to the carwash! 

http://bama.edebris.com/manuals/military/r390/

[w1vtp]

I tried the break in method using the barrier strip terminals on the back. It does nothing. The RF gain/relay contact method does work though. Now that you mention a possible problem to the RF gain pot being caused I am now skeptical. Does anyone have any idea why the break in method doesn't work on my 390?
This is a non-A model, early serial number #1023

<deleted comments> OOPS  wrong receiver. My comments were for the Hammarlund SP600

Al

[N6YW]

Al, by all means do tell. I plan to use the 600 in the same fashion.

[The Slab Bacon]

(390As)

Check the selenium rectumfryer near the built in antenna relay. They have a tendancy to crap out for no reason. and if so, the antenna relay / break-in won't work. Replace it with silicon diodes, 4000 or 5400 series.

[Ed/KB1HYS]

I use a Valiant here with an R-390 in Break in.  The rig provides a relay out (110v) that I use to actuate a DPDT reed type relay.  I use the relay to trigger the R390's internal break in via the terminal strip and to ground the receivers antenna input.  The only down side I had was that the relay would reverse a little too quick on key up and I'd catch some RF in the receiver, I tried a couple of different relays and then just ended up bending the reeds lightly to slow down the transition. (KISS in effect).

Been very reliable.

For some situations, it can be handy if you ground the break-in terminal on the back of the R390, then you can then control the receiver directly from the front panel via the break-in switch.  

Also, IMHO one of the best R390 manuals out there is the Y2K version, which is basically a rewrite of the military manual with some extras thrown in.   I liked it so much I actually printed and bound one out of the PDF file I downloaded.

[KM1H]

Im using the rear contacts and front panel switch also on my odd contract # R-388.

Carl

[Todd, KA1KAQ]

I tried the additional method of opening the RF gain contacts on the rear apron and believe doing so caused some problems. The RF gain pot on the front panel tends to burn a spot on the resistance substrate in the pot.

First I've heard of that. It shouldn't be an issue. Maybe a bad pot left in one spot for a lengthy time as with so many of these and other sets?

(390As)
Check the selenium rectumfryer near the built in antenna relay. They have a tendancy to crap out for no reason. and if so, the antenna relay / break-in won't work. Replace it with silicon diodes, 4000 or 5400 series.

Good point. The antenna relays have known to fail open, too. But the rectifier is a good place to start if it won't respond.