sx850 sx950 awf011 phono replacement parts
When I had the unit recapped the phono section was "bypassed" in that I didnt have a TT then -- and now do! The tech said the phono sections was, I forget exactly, but "had issues." The quality/clarity, is there but with nothing playing and the volume even up moderately it sounds like wind thru a microphone on a windy day. Also there is random bouts of harsh crackling thru the speakers -- particularly the right channel that occurs at no particular point in the record but is loud and just plain irritating. Cant live with it. Now in any other mode, Aux, FM, etc it is perfectly fine, quiet, no such issues. Is this familiar to anyone? I am likely not going to repair this myself, but will it likely be an expensive repair...due to parts issues or ??
Well, IF you were going to do it yourself, and had soldering / desoldering equipment, you could get away with spending far less than 10 bucks (edit $3.16 w/o ship) in parts, excluding shipping. There are SEVERAL threads on the Pioneer forum about rebuilding the phono amp in the 850, 950 and several remarkably similar phono's on other models. Board # AWF011
But it's not fair to compare the costs of parts where I get my parts and the substitutes I have found that work with a shop's supplier OR a shop's overhead in keeping the parts in stock.
If you have someone else do it, they'll probably take an hour of shop time to do it, at 45 bucks an hour (or more) shop rate.
The phono section is well exposed on the sx950, and after freeing it from the plastic clips, there is plenty of room to work on without disconnecting wires.
Basically the 2sa725 transistors are getting noisy, and working themselves up to a full blown failure.
from mouser.com
Q1, Q2 : 512-KSA992FBU (low noise)to-92 ecb 120v .05a .5w 100mhz 150-800hfe $0.06 ea
Q3, Q4, Q5, Q6: 512-KSC1845EBU (low noise)to-92 ecb 120v .05a .5w 100mhz 150-800hfe $0.06 ea
C1, C2: 1uf 25v 647-UPW1H010MDD 1uf 50v $0.23 ea
C7, C8: 330uf 6v 647-UPW0J331MED 330uf 6.3v $0.39 ea
C11, C12: 3.3uf 25v 647-UPW1H3R3MDD 3.3uf 50v $0.23 ea
C17: 100uf 35v 647-UPW1H101MPD 100uf 50v $0.50 ea
C18: 220uf 25v 647-upw1h221mpd 220uf 50v $0.60 ea
all are currently in stock, changes in voltage reflect either availability or cost versus safety margin tradeoffs.
Note: the transistor lead arrangement on the originals are bce while the replacements are ecb, meaning the flat faces the other way
and the caps are polarized, look for the plus on the board and remember the MINUS lead is marked on the capacitor, be sure the board markings reflect the way the cap you are removing was installed.
The other alternative is to remove the board yourself, send it to me and I will re-do the board BUT you STILL have to solder the wires back onto the board correctly, in the holes where I will remove the pins for you. It isn't that much work to do the caps and transistors WITHOUT disconnecting any wires.