pioneer sx1500td blowing fuse
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Joined: Nov 2012
City: Kansas city, MO.
While waiting for trim pot order to arrive I was checking around on the chassis looking for anythig I might have missed. I have AM but no FM. With power on I discovered that the control amp board W15-079 caps C3 & C5 and transistor Q1-2sc871 when touched or tapped make a hum and scratching sound out of the speaker. This is with unit in FM mode.
I'm going to recap this board and replace the transistors.
Heres the question. There are 2-2sc871 and 2-2sc870 transistors on the board.
The searches for replacements show use KSC1845 for all four transistors,but 2 of them are pnp.( the 871s) according to schematic and KSC1845s are npn.
[Image: http://i1336.photobucket.com/albums/o654...cd640d.jpg]
Here is schem. What should I use for the pnps? Or am I misreading schem.?
Thanks.
Messages In This Thread
RE: pioneer sx1500td blowing fuse - by KCMike - 01-28-2015, 12:57 PM
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Hello Tim,
I would if it's a leaky Capacitor So are all 3 of those B- voltages low then ?
Sincerely Richardradiorich — 01:55 AM |
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I'd try replacing the bulb first and if that doesn't do it, then change the 35Z5 and see if the problem goes away.NostalgiaRadioTime — 12:28 AM |
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Hello Tim,
I have that exact unit in my shop too plus a Sencore unit there are times I like one or other !!.
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I suspect it's been repaired before.
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Thanks Rich! I'll take a look and see what he has. I know there's more modern equipment to be had, but this one I know a...TV MAN — 09:11 PM |
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Hello Tim,
Here is a link to restoration of one on Phil's old radios site !
Sincerely Richard
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I'm a little befuddled on this one. Should X5 and X4 be tied together like this? It looks like someone added this at so...R3Sons — 07:33 PM |
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