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Now What?? My 250 is down, again.

forceof1

forceof1

Active Member
I had my 250 restored only 5 years ago. The left channel began would drop in and out in the worst times. I recently noticed sound from my iPad coming through from the Aux when I'm in phono. Two nights ago the left channel volume was very slight in comparison to the right. Now I have virtually no amplified sound coming through. My 250 pairs with a 3250B that was just serviced.

Wish I knew more about what happens and why in these situations. Got any info? Thanks!!
 
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Old stuff breaks. Get used to it.
Can you connect the iPad directly to the amp, and
start with the volume down very low. This will test
To see if it's the amp or preamp. Did they replace the
protection relay when they worked on the 250?
 
Not all restorations are the same.

The relay is a good place to start. If you know where it is, take a popsicle stick or chop stick and press on it a bit while playing and see if that makes a difference.

The below is a 250M
B4D40451-3BE5-47B9-9CE1-A1977CB01A54.jpeg
 
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forceof1 said:
I had my 250 restored only 5 years ago. The left channel began would drop in and out in the worst times. I recently noticed sound from my iPad coming through from the Aux when I'm in phono. Two nights ago the left channel volume was very slight in comparison to the right. Now I have virtually no amplified sound coming through. My 250 pairs with a 3250B that was just serviced.

Wish I knew more about what happens and why in these situations. Got any info? Thanks!!
Click to expand...
Take it back to the guy who "restored" it. If he's worth his salt he'll make it right.
 
Coolhandjjl said:
Five years is an awful long time. Longest I know of is a 1 year, and you have to pay to ship it there.

The work he did may still be fine, but it’s well within the scope of things for other components to go out, even if they were operational when he had it.
Click to expand...
Must not be a good restoration if it can't even make it five years.....it's not a awful long time considering the amount probably paid and the fact the unit is pushing 50 years old.

Someone could come back with the first restore I did, and unless they personally blew it up, I would fix it again, no or low cost.
 
forceof1 said:
I recently noticed sound from my iPad coming through from the Aux when I'm in phono. Two nights ago the left channel volume was very slight in comparison to the right. Now I have virtually no amplified sound coming through.
Click to expand...
The 250 is only a power amplifier. All of the input switching is done in the 3250B Pre-Amp. So, if you suspect audio signal leakage, it would be in the 3250B Pre-Amp circuits... not the Power Amp. Since you just had it serviced, I would suspect a problem with the Preamp.
As @keitht says, connect your iPhone directly to the inputs of the 250 (with iPhone volume turned waaaaay down) and see if both channels work. Otherwise, your problem is in the Pre-Amp, as @kwayde suggests.
BTW... do you have your speakers hooked up to the 250 or are you using the 3250B to select speakers? It could be dirty speaker selector switches. Try to connect up to the other speaker terminals or try with headphones.
 
keitht said:
Old stuff breaks. Get used to it.
Can you connect the iPad directly to the amp, and
start with the volume down very low. This will test
To see if it's the amp or preamp. Did they replace the
protection relay when they worked on the 250?
Click to expand...

kwayde said:
Are you sure it's the amp and not the preamp?
Click to expand...
Ok, I've isolated the amp, it's fine. the preamp needs to be looked at. At this point with audio leaking across inputs and the loss of a channel I'm guessing it's pretty serious? (fingers crossed).
 
dankik said:
The 250 is only a power amplifier. All of the input switching is done in the 3250B Pre-Amp. So, if you suspect audio signal leakage, it would be in the 3250B Pre-Amp circuits... not the Power Amp. Since you just had it serviced, I would suspect a problem with the Preamp.
As @keitht says, connect your iPhone directly to the inputs of the 250 (with iPhone volume turned waaaaay down) and see if both channels work. Otherwise, your problem is in the Pre-Amp, as @kwayde suggests.
BTW... do you have your speakers hooked up to the 250 or are you using the 3250B to select speakers? It could be dirty speaker selector switches. Try to connect up to the other speaker terminals or try with headphones.
Click to expand...
@keitht Thanks for the help! My speakers are to the 250. I've isolated the amp, the pre-amp is the problem. With that being said I have a failed channel and audio leakage across inputs. Any idea of how serious this is? I really appreciate your help.
 
Great... so now the 250 is in the clear! Let's see if we can narrow down the part of the Pre-amp that is giving us the problem. Here are some questions to help isolate the problem:
  1. When you hear the weak channel, where did you have the speakers connected,... to the 250 or the 3250B? Edit: Answered above^^^
  2. forceof1 said:
    Now I have virtually no amplified sound coming through
    Click to expand...
    Do you mean no sound through only the Left channel, or both channels?
  3. If you listen through headphones plugged into the "phones" jack of the 3250B is the L channel clear or weak also?
  4. If you put the Mode selector into "Reverse" does the bad channel (L) change sides (to R)?
  5. If you put the Mode selector into "L" do both channels sound bad. Likewise, if you put it to "R" do both channels sound good?
  6. If you connect your iPhone outputs into Tuner, does it sound any different (still bad L channel)?
  7. forceof1 said:
    I recently noticed sound from my iPad coming through from the Aux when I'm in phono.
    Click to expand...
    The phono input has a high gain since it has to amplify the small cartridge output voltage so any stray signal can leak into the phono channel. We'll get to that later.
  8. What kind of service did you have on your 3250B? new capacitors, new transistors, Deoxit controls? Sometimes the balance control goes bad and one or both channels go bad.
  9. One last thing: If you push-in the Tone Defeat button, does it change anything?
  10. One last, last thing: if you put your iPhone (turn volume DOWN) into Aux and plug 'Tape 1 Out' into your 250 does it sound OK?
 
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dankik said:
Great... so now the 250 is in the clear! Let's see if we can narrow down the part of the Pre-amp that is giving us the problem. Here are some questions to help isolate the problem:
  1. When you hear the weak channel, where did you have the speakers connected,... to the 250 or the 3250B? Edit: Answered above^^^

  2. Do you mean no sound through only the Left channel, or both channels?
  3. If you listen through headphones plugged into the "phones" jack of the 3250B is the L channel clear or weak also?
  4. If you put the Mode selector into "Reverse" does the bad channel (L) change sides (to R)?
  5. If you put the Mode selector into "L" do both channels sound bad. Likewise, if you put it to "R" do both channels sound good?
  6. If you connect your iPhone outputs into Tuner, does it sound any different (still bad L channel)?

  7. The phono input has a high gain since it has to amplify the small cartridge output voltage so any stray signal can leak into the phono channel. We'll get to that later.
  8. What kind of service did you have on your 3250B? new capacitors, new transistors, Deoxit controls? Sometimes the balance control goes bad and one or both channels go bad.
  9. One last thing: If you push-in the Tone Defeat button, does it change anything?
  10. One last, last thing: if you put your iPhone (turn volume DOWN) into Aux and plug 'Tape 1 Out' into your 250 does it sound OK?
Click to expand...
Powered it up to follow your instructions but it's working, of course. I'll keep it going until it fails and get back to you. Thinking through "service" I took it in just to have it looked at and no issues found. That was about a year or so ago. Now I really need it serviced! I'll get back to ya when I can answer your questions. Thanks again for your help
 
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