Dead 2220B. What should I do?

Onebean

AK Subscriber
Subscriber
I picked up this 2220B in a package deal, and the guy told me it was dead. After reading lots of threads here, about resurrecting dead units, I assumed it could be fixed. Here are some pictures of what I have.

Faceplate looks very nice.



Inside top, not so much. :eek2:







Then I pulled the bottom cover.



So I assume with all that dirt in there, every pot is full, preventing signal to pass. What should I do? Is there a way to clean all that dirt off without damaging the components? It's stuck pretty good, I rubbed on one of the circuit boards to see how stuck it was, and it came off, but not like dust. Air blast isn't going to do much of anything.

My goal is to get it going with minimal cash outlay. Where do I start?

Onebean
 
@Steven Tate and others have successfully washed receivers. I'm sure one of them will chime in with their experience. Personally never tried it but you might have nothing to lose in this case.
 
That's a wash unit. Remove face as well. Use a product called Simple Green and a couple of soft paint brushed. Spray brush and rinse with a garden hose. Avoid spraying the transformer. Let dry for a week in the sun if you can. Some put in a low temp oven to dry, I have never done this.
 
Dim Bulb Tester. You make it from hardware store electrical parts. It is basically an electrical outlet, a light bulb and a switch. Wired properly, you plug an audio device into it rather than a wall socket. When you power up through the DBT, the bulb will be bright for a few seconds as caps charge up. If there are no shorts in the system, the bulb quickly dims. The unit passed the test, and you can probably plug it into a wall socket safely. If the bulb stays bright, something is shorted and you may have just saved your unit from destroying components. DBT should be used on any new-to-you piece of equipment when powering up the first time and every time you work on it to be sure nothing is shorted. Google Dim Bulb Tester Plans and you will see many articles and YouTube videos.
Steve
 
I did the 'wash' with windex and a small paint brush, it worked well, but things dry out pretty quick here in AZ, I would let it sit for 3-4 days after the wash before you test it. Be very carefull around the tuner (air only). A DBT will cost you about $10.00 to make and can save you $$$$$$, can't recommend it enough. Good Luck and welcome to the restore addiction. Rich
 
Steven, no magic smoke released, and the lights came on, but no signal was passed to the speakers.

Richs, I purchased supplies for the DBT tonight. I'll assemble it tomorrow night time permitting, and see what the light does when I flip the switch.
 
A good cleaning followed by de-oxit treatment (look up de-oxit on AK) and you might get sound. Remember to treat and then work each control repeatly, let sit a few minutes and then give it a try on the DBT (I used a 60w bulb for small amps and 100w for larger ones), if the light goes dim, try it on real power (although it will play while connected to a DBT, voltage may be irregular and sound may be distorted and have a hum). If still no sound, re-check all you switches i.e. tape monitors off, selector in fm or aux, speaker selected and then try working each switch and control one at time and see if you get any audio. If you do, clean and work that control again. good luck Rich
 
Ok, I built the dim bulb tester and plugged the 2220 into it. Here's a video.


Looks like I'm good to go other than cleaning up the pots and switches.

What are these pots?




Can someone point to a tutorial on setting the bias on this unit?

Onebean
 
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You can get the service manual at hifiengine.com for free, you just have to register. That board is P-200 and part of the FM circuit. It is best to keep moisture away from the tuner sections and not change any settings. The bias and dc setting will be on the power amp board P-700 (has the heat sink) and hifiengine will get you the procedure with the SM. Good luck (glad it passed the DBT, you can plug it into real power and see if it has sound, but if you do the wash, DBT it again before trying to use it) Rich
 
Any time you perform any service or changes, it is always good to DBT, it only takes a minute and will save your equipment from serious damage.
 
i would get it in the shower set on hot ..plenty of washing up liquid and a paint brush ... rinse it well .. blow dry with air compressor ..spray down with iso ... blow dry with hairdryer then leave in the warm a few days .
only use iso outdoors ...
 
So I did some disassembly and got some Deoxit into the pots and switches. The switches are not the easiest to access, so I sprayed them from the front side. Still no signal pass. I can here a relay kick on after I turn it on, and a couple more of the lights have started working. Any ideas what else might be causing the lack of output? I'm assuming it's still a dirty pot. I was hoping to get some kind of signal to pass through it, before I start washing it down.

Onebean
 
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