FT-102 help

[W1RKW]

Got an FT102 that is acting flakey.  It seems to have intermittent receive or weak receive.  No matter where in or on the chassis I tap and as lightly as I tap the receive audio cuts in and out.  I suspect the problem to be on or near the driver board where the infamous relays are. Though I'm 90% on this.  As far as I can tell the relays check OK.  And had been replaced a few years ago.  Wiggling various wires and cables seems to give the same result as tapping.  Transmit check OK. Any common problems with the FT-102 anyone know of?  Thanks.

[K1JJ]

Hi Bob,

Trying pushing lightly with an insulated rod to zero in on the loose connection.

You might also try that cold spray for a lighter touch.

It's usually the relays  -  but maybe a blob of solder shorting something or a wire that is crossing a track.

Fortunately, these kinds of problems are easier to find than say a component that is lossy.

Good luck -

T

[W1RKW]

Tom,
I think I've zero'ed it down to a connector on the driver board. I don't know that for sure because I haven't pulled the board yet and I'm not looking forward to pulling it out.  The connector feels tight when plugged in but I'm suspecting possibly a poor solder connection on that connector on the solder side of the PC board.  Is the FT 102 prone to bad solder connections?

BW

[K1JJ]

Yes, there's lots of plugs and wires that go directly into the boards. Like some radios of the era it's known for this problem.

I've had my share with four FT-102's here, but for the last few years they have all behaved.

T

[W1RKW]

Thanks Tom,  I'm pretty sure now the  problem is located at this connector.  If I put a little pressure on the outside of it and wiggle the wires that plug into it the problem goes away.  And also while holding it and tapping the board there seem to be no cut-outs.  Now I have to work up the nerve to pull that board out.  It's really crammed in there. 
Thanks.
BW

[WA1GFZ]

Spray deoxit on all connector contacts. The plating breaks down over time and causes poor connections.

[W1RKW]

Well,  I found the problem.  Definitely a cold solder joint on the connector mentioned in a previous post.  Went through all the trouble to try to remove the relay/driver board and discovered that the solder side of the board can be accessed from underneath by removing a plate in the chassis.  So I had to reassemble everything I took out but got to the solder side of the board and resoldered all the suspicious looking solder joints.  Rig is back to normal.  Thanks for the help.
B

[K1JJ]

Yes, I found the same thing on a few boards that held heavy components. As you know, that is a weakness of the hybrid tube/solid state era. It's good you successfully got at the board and took a shotgun approach to resoldering the suspect connections.

All in all, the FT-102 sure has a FB receiver. It's worth maintaining. I see no difference between them and my FT-1000D. (Except for the 1000D's weighed dial and dual diversity reception).

T

[W1RKW]

I've noticed with a lot of components that have a big lead and might carry some current through it they have a tendency to end up with cyrstalized solder connections.  And then there are those leads that aren't bent over to make a mechanical connection, they also seem to end up with weak solder joint.  A simple reheat and application of some 60/40 fixes everything. 

I'm very happy with the rig overall.  I bought it used, probably 15 or so years ago.  It worked fine when I brought it home.  I've had a few minor problems with it during that time most of which have happened in the last 7 or so years.  Relays were replaced and have never had a problem with them.  Had an audio problem last year caused by a bad cap.  And recently a couple of poor solder connections.  Overall I can't complain.  The problems have been simple to fix and the rig keeps on tickin'.  The receiver can't be beat, no doubt about that.  Just wish I could use it much as I'd like...