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Any experienced tech should be able to change them no problem.

Check the main filter caps along with all the power supply capacitors, also check for any broken ground wires or any grounding screws not properly tightened down.

The relay is engaging so it is working. measure the dc offset when the amp is in protection ( relay disengaged) which you cannot do at the speaker terminals, easiest way is to check dc offset at one of the emitter resistors or where ever the amp output reaches the protection circuit. Also check...

beware of those ebay kits, I never order any but have had customers bring them to me even though I specifically ask that they don't. The 3 kits I have worked with only 1 was any good, the other 2 either had missing parts or not the correct parts or had very cheap brand components. A lot of those...

what is your power supply issue? This forum is the correct one for anything pioneer.

on the speakers, 120hz hum

I have this sansui on the bench for restoration, the unit came in working pretty well other than the typical dirty controls and had some highish dc offset but other than that no issues where found at the time. so I went ahead and started my basic rebuild, all power supply caps, driver board...

sounds like you probably have excess dc on the signal in the preamp check caps if you replaced any for polarity, and check for bridge solders or a bad capacitor.

Also check your main filter caps, that can cause a hum in both channels if either one is going bad.

so when the RHS outputs are in the relay clicks immediately and you have 37 volts on the outputs? If there is that much dc the relay shouldn't engage at all.

You said the protection relay clicked in but your have 37volts of dc offset?? I would go back to the power supply and check all your voltages and compare to the schematic, maybe have a cap in backwards?

First off if the bias is getting to 42volts on the left channel do not run the unit anymore if you haven't already you will blow all the work you have done, first thing to do disconnect all wires from the power supply other than the input voltages, and make sure you have the correct voltage on...

check c8 and c9 the 2 larger 470uf caps those seem to always fail on these, along with the 2sd313s. I always just recap the power supply and replace the 313s on any units in this series they all need it at some point or another.

working on a this 2238b just giving it a tune up and basic maintenance. I have everything solved except one problem the signal strength meter doesn't work on Am. On fm works fine brining in perfect stereo stations and after doing a basic quick alignment. I do bring in am stations not many around...

working on one of these big rotel receivers. Doing a full rebuild which means changing out the old trim pots on the amp board. But ran into an issue the garbage service manual does not give and info for doing these adjustments. wondering if anyone out there has worked on one and has done the...

little bit of back story, a buddy of mine owns this unit in which the digital readout on the tuner is stuck ( see attached Images) he told me the it worked perfect before he changed out the quartz lock bulb in the front. After changing the bulb the display is now stuck both am and fm. The tuner...

Working on this rare beast that has blown both driver boards and i am looking for same hard to find transistor substitutes. 2sb717 2sd757 2sb719 2sd759 Also looking to find some information on the dual 5 pin transistors that are used 2sa995 2sa979 2sc2259 2sc2291 Any help would appreciated

When swapping the amp modules, everything from one channel to the other goes the driver board and outputs all come out as one and i simply swapped them left and right so everything would move. so yes the outputs moved with the channel. I will have to take a look at pins 4 and 5 on the driver block

Installed the jumper between pin 11 and 12 issue is still present.

Whats components on the meter amp board would be most likely to cause this issue I have tested all of the transistors on the meter amp board none are totally failed so guessing its one of those looks good on a meter but wont actually work. What on the board works with the protection circuit...

Well i scoped out the supply for the left side rectifiers are working properly. So last thing to try is the relays and see if the left channel relay is the one at fault. Just to clarify The 2 relays that sit in the middle of the unit between the caps there is one for each channel correct. I...

my mistake both relays are clicking in as they should. But seems now when applying a signal to the channel it will go up to a certain point then the relay will click out. On the Vu meter for the left channel when increase the volume the meter will go up then slowly drop down and the relay will...

Ok i just did notice the small relay that is on the driver board for the left channel is kicking in about 5 seconds after power up. so obviously the only sound i am getting is what is bleeding through it im guessing. now the question is why.

I checked the speaker Jacks no shorts. Just got done testing the filter caps and all of them are ok even quickly swapped in some new ones i had laying around but still had the issue. grrrrr this ones stumping me. just for reference here is a pic of the sine wave from the left channel. The meter...

The volume control does not impact the distortion even if turned to max. I have checked all my power supply voltages they are the same on both channels it seems. by the way just to describe the distortion the channel is very fuzzy sounding and very low power. Maybe one of the main caps is going...