[TenTec] Paragon output problem

[Mike Bryce]

vic,

I don't have the paragon manual in front of me, so, doing this from memory.

on 40 and 30 meters, the same relays control the L/C components so, if it is a relay problem, you should see it on 30 meters as well.

do what Wade suggested by stuffing the RF into a dummy load and seeing what happens

on the low pass filter board there is a large MTA cable that carries the band information. When you switch bands, one line after another will go to +12 or so.

these band control lines run all over the place. They select the bandpass filters for the front end, the low pass filters for the output and so on..

measure each one, and as you change bands, one should go high, then change bands, that one should go low and the next one high as so on. YOu can see what one does what on the schematic.

basically, you want the 40/30 meter line high and no others.  and when you change bands, the 40/30 meter line should go and stay at zero volts.

If all seems like it should be, there's not much else you can do unless you pop the low pass filter board out from it's little nook. There's usually enough slack in the wire to allow you to reconnect the filter board after you have it removed from the chassis. use some cardboard to prevent shorting out the board to the chassis. 

using your vom, while on 40 meters observe if there is 12 volts going to the two relays that control that band. if your hearing is good, you can sometimes hear them click in. Trouble is, you can't tell by listening what one clicked and what one didn't click.

to find which one is bad, set you vom to continuity. from either input or output side of the filter you should see less than a few ohms. If you don't see that, then one (or both) of the relays hasn't closed. work your way from one side to other as you look for the open relay contacts.

I've fixed quite a few of these before and the damn thing is many times, the relay will actually close and you can see continuity across its contacts, but it won't work in the radio.

by the way the relay's  coils are wired in series.

Ten Tec has these in stock. They're not cheap, so before you order in parts, make sure you found the problem.

mike, wb8vge


On Nov 16, 2012, at 10:25 AM, Wade Staggs wrote:

> *Hello Again Vic,*
> *                            Since nobody else has jumped in to comment
> further. If your problem is only happening between 6.5 and 10.5 Mhz. It is
> my belief that on the Low Pass Filter board of your Paragon 585. Relay K10
> or K8 are the most likely cause of your problem. Also, check C45, L9,
> L8,C44, C42, and C47  on the Low Pass Filter Board. Loose connections are
> not a normal problem on this Board that I know of but, don't rule that out.
> If the problem is happening outside of the 6.5 to 10.5 Mhz. frequencies on
> Transmit. I could be bad solder connections or a connector between the PA
> Stage and the Antenna Jack including the Low Pass Filter Board. 73 to you
> Vic, and please tell us how things work out.*
> *
> cul de Wade/KJ4WS*
>