Pioneer SA-5300 input problem

[mlon]

howdy all!

i bought this pioneer amp for a few bucks knowing it was faulty and
since i like fixing (and breaking) stuff i thought of giving it a go and try to get it working again.
so i hooked it up to test it and nope, nothing... hmm, blown?
switched inputs from aux to tuner, nope.

than i had the illuminous idea to try it with tape input.. tadaa!
everything works! not even crackling knobs! functions perfectly!

after scouring the pcb i could not find anything obvious.
there are these 2 long green and blue cables taking a different path going to the pcb... they are the working tape inputs.
but i cant figure out why the other inputs arent working.
so, do you guys have any idea where to look?

thanks in advance!!

mlon

 

[markthefixer]

first - get the service manual (if you can find it, also the owners manual and schematic (sa-5300 and sa-6300 from hifiengine).

second - clean EVERY switch with deoxit. It's probably the rotary function switch (wafer switch - BOTH sides of the wafer!), since the tape monitor connections provide an output signal that is selected by the function switch.

then if it still happens, use an ohmmeter to trace the path from an input jack (aux, tuner?, NOT the phono - it has an additional amplifier circuit before the function switch.), through any cables that go on AND OFF and back on the board.

 

[mlon]

hey thanks mark!

i will let you know what the findings will be!

mlon

 

[Tony75]

Just a silly question...
Is the tape-monitor switch on?
That would explain why it works on tape input and not on others.
If so a very easy fix:yes:

 

[sallog]

first - get the service manual (if you can find it, also the owners manual and schematic (sa-5300 and sa-6300 from hifiengine).

second - clean EVERY switch with deoxit. It's probably the rotary function switch (wafer switch - BOTH sides of the wafer!), since the tape monitor connections provide an output signal that is selected by the function switch.

then if it still happens, use an ohmmeter to trace the path from an input jack (aux, tuner?, NOT the phono - it has an additional amplifier circuit before the function switch.), through any cables that go on AND OFF and back on the board.

I have problem with this Pioneer SA-5300. The only input that works is the cassette deck(PB). I have cleaned all the switches and pots thoroughly but no joy. I have tried toggling Tape monitor on/off but AUX, PHONO and TUNER does not work. I have replaced PSU caps but still no luck. Checked board for dried joints , there were a few but that did not fixed the problem. I have noticed that this amp is employed with pre-amp ha1452 ic chip..do you think this is the the problem? One of the pinns read about 15v. Please any help much appreciated. I have replaced all 4 Sanyo caps (1uf/25v) as well. But no luck!

 

[zebulon1]

The issue is in the switching.
Caps have nothing to do with it.
If the set utilizes the remote ribbon switches. Look closely at the mechanical motion for correct rigging or damage.

 

[petehall347]

probably the tape play switch as this one is less used and if moved when its been still for a long time it loses connections . same as any other switch for that matter .

 

[sallog]

Switches are a simple mechanical type (still operates smoothly) and I have tried to override the path by shorting the pins but no joy. Loudness switch does not work either. This was working absolutely fine 3 days ago. Do you think its ha1452 ic chip or is it dust? BTW when you connect AUX and select AUX (Tape monitor off) the source comes through but very quiet.

 

[sallog]

View attachment 971036

 

[sallog]

Switch cleaning did not help. I let it dried and used Air duster the following day and . Problem solved - dust. Thanks for your support lads.