Fisher X202B

Hi Folks. Tonight I turned on my beloved X202B and I immediately knew something was not right. As I started Spotify and played some music I decided it was too loud and went to turn it down but the volume wouldn't turn down all the way. Still quite loud. Then I turned the tape monitor switch off and got a hum from the speakers. I waited a few minutes and turned it back on. I tryed switching from Aux 1 to Aux 2 and still got music along with the volume not regulating correctly. I also tryed the tuner selector on the amp and still got music. Mind you, the tuner connected wasnt even on. Music is bleeding thru on something and dont know what to do other than shut it off. I also tryed a CD player and got a little music but mostly hum from the speakers.

This amp was restored a year or so ago and has always preformed perfectly till now. I only use it on weekends. Cant for the life of me figure this out. Any ideas? Thanks AL

Al -- If you will, please describe the condition in more detail, considering:

1. With the volume turned all the way down, is it still rather "normal" loud?, or

2. Blasting?, or

3. It does turn down, but you still hear the selected source faintly with a rather tinny character to it?

Also, does the loudness function still operate correctly or not?

These can all be caused by different situations.

Let us know!

Dave

Hi Dave, yes when the volume is turned down the volume is still "normal", no tinny sound at all. Normally the volume worked just fine. Also, I did try the loudness switch and no difference between off and on. In addition, When this was all going on I tryed the selector switch and the Aux 1 and Aux 2 made no difference, I still got sound which I shouldn't have. Also has the same sound on the same selector switch when placed on tuner..yeah I know, sounds crazy. Also the hum, cant figure that out either..

This amp has been perfect until tonight, I know I'm a rookie but am trying to figure out what happened. This amp gets maybe 6 hours use a week..always spot on til now.

From what i have learned on here it could be the volume switch? I sure hope not. Even if it is why the hum? Thanks Al

Al -- Very doubtful that the volume control itself is bad. This smacks of a bad ground connection -- Inputs not being grounded out when not selected, the volume control "low" terminal not grounded as it should be, etc.

Fisher often daisy chained various terminals together that needed to be connected to ground, and then grounded the daily chain in just one place, but that practice ended with the X-202 if I remember correctly. In any event, this is almost certainly about a bad ground connection.

If you are up for it, with the amplifier upside down and the bottom cover off and operating (be careful!), us a simple clip lead to connect the low side terminal of either channel's volume control to the chassis. With the three terminals facing up at you, and looking from the back of the volume control, this will be the left terminal in the group of three.

If that corrects the volume issue, then it proves there is a compromised ground connection somewhere in the line/tone stages of the unit.

While I'm not trying to make lite of the issue, this should be a rather simple problem to fix.

I hope that helps!

Dave

Thanks Dave, don't think I have the skills for that and no leads to clip either..will PM you tomorrow. Thanks very much Al Still learning here...

Did the restorer offer a warranty? Although it does not appear the problem is related.

Morning Folks, thanks for the help last night, going to pull the bottom cover off this afternoon and post pics. Sure am befuddled over this as it's the first time its acted up. Will check best I can for ground issues buy frankly everything's hooked up as its always been. Maybe pics will help...:scratch2:

Ok let me see if I can upload some pics.

Hope those pics might determine the hum I have in this amp, unhooked and re connected all cables this afternoon to see if that helped. Obviously it didn't. This amp sounds as good as anything I have ever heard, now this.. if you guys see anything please let me know and thanks AL

Nothing immediately jumps out, Al. If you can, pull the top cover and get a good shot of the volume control, as the problem could easily be in that area as well.

That's a beautiful X-202B!

Dave

Ok will do.be tomorrow though and thanks!

Pics of Volume control area, best I could do.

Pics look like you know what, hope this helps though and thanks Al

Still nothing obvious, but with the loudness switch not operating, it must be a ground issue in and around the volume control circuit. Fisher often used the ground side of shielded cable to make a ground connection at one end, from an actual ground connection at the other end. That means that if the ground wire within the shielded cable breaks, it can be the same thing as a bad or ineffective ground connection. Or, it means that the actual ground fault could be quite a ways away from the circuit that is faulting. It will likely take an Ohmmeter to track the fault down.

Dave

There is a broken black cap...

second cap from the pot?

here

All I see is a blob of solder, like they missed putting it on the volume control back cover and it got on the lower part of the volume pot.

Tube

Looks like the brown cap has a cracked housing.

Thanks guys, the loudness switch has always worked fine, the other day though it didn't to work when I was fiddling with it. The brown cap looks to me anyway an original so maybe that has something to do with it. Will get it fixed very soon and off to repair it goes.

Thought I would make a update on my X202B this afternoon. Yesterday my wife and I made a 4 hour road trip down to Georgia with my 2 "kids" aboard. That being my X202B as well as my 800C. I got the distinct privilege of meeting our own Fisher expert Dave Gillespie. Dave has a beautiful home and as we have all known for quite sometime he is a expert on things Fisher and audio as well. We spent almost 4 hours talking and going over my gear in which he is repairing as he would his own gear.

After talking with Dave I was just plain in a state of Awe on his knowledge of circuits and how things worked on this hobby of ours in this Forum. I learned more from him in 4 hours than I've ever learned anywhere else, I left inspired to learn more and it really was a treat to see his Fisher equipment as well as the amps and clones he has designed and built on his own. To see the amps he built look like something off a showroom floor, no detail left untouched. Then I also got a chance to see the "closet". a secret room if you will that houses nice gear as Eico, more Fisher, the mighty Bogen as you all remember. A visit to Dave's is like a museum in all things audio.

All this being said, I got home last night and wrote down all I could on what I learned, will remember yesterday forever I am sure. We are truly lucky to have Dave here in this Forum. Thanks again Dave.