I have a 500sx that seems to short circuit when I hook it up to the power supply, as the analogue indicator of the PS instantly maxes out at over 3 ampere, the max indication, so I quickly power it off.
I see this one has been heavily repaired in the past.
Anyway, I once had a Ref 300 and 200s which also short circuited, and on both amps replacing the rectifiers did it for me.
I can't remember what the rectifiers should read on this amp, as it's quite some time ago, but when I did the ohms test I only had 0.00 or 1 (max) on the digital multimeter, nothing else. Usually there are also other values. Many, many legs have 0.00 on them, in several directions. So maybe the rectifiers need to be replaced on this one as well ?
I noticed they are FEP16CT and FEN16CT, I have lots of BT's in stock but they are lower rated. Wonder why Jaime give me so much BT's, while most Ref s / sx amplifiers use the higher rated CT and DT ?
I have some DT's in stock I think, could use those. Or would it be safe to use the lower rated BT's ? Got so many of them...
I see the 160s and 200s use BT, but most (if not all) other models use CT or DT, and more often DT than CT. Wonder what I will ever use the BT's for ??
I see this one has been heavily repaired in the past.
Anyway, I once had a Ref 300 and 200s which also short circuited, and on both amps replacing the rectifiers did it for me.
I can't remember what the rectifiers should read on this amp, as it's quite some time ago, but when I did the ohms test I only had 0.00 or 1 (max) on the digital multimeter, nothing else. Usually there are also other values. Many, many legs have 0.00 on them, in several directions. So maybe the rectifiers need to be replaced on this one as well ?
I noticed they are FEP16CT and FEN16CT, I have lots of BT's in stock but they are lower rated. Wonder why Jaime give me so much BT's, while most Ref s / sx amplifiers use the higher rated CT and DT ?
I have some DT's in stock I think, could use those. Or would it be safe to use the lower rated BT's ? Got so many of them...
I see the 160s and 200s use BT, but most (if not all) other models use CT or DT, and more often DT than CT. Wonder what I will ever use the BT's for ??
You can send all of your BT's to me if you like lol lol..
Most amps like SoundStream only have 20 to 35 volt rails so lower PIV rated diodes should just fine my friend
Using a 600 PIV rated diode means the engineer spec'ed the highest rated device possible in hopes of getting the best possible PN junctions off the silicon wafer, and inside the amp.
Most amps like SoundStream only have 20 to 35 volt rails so lower PIV rated diodes should just fine my friend
Using a 600 PIV rated diode means the engineer spec'ed the highest rated device possible in hopes of getting the best possible PN junctions off the silicon wafer, and inside the amp.
In the circuit, you will read 0.000v on diode check across the outer legs because the transformer windings are connected to those legs. Although there are a few exceptions to this, most amps that use positive and negative center-tapped rectifiers connect the transformer windings to the outer two legs.
Great information Perry.
I'll have to check but I think I have lots of positions on which it read 0.00 ohms.
When you're saying that I can expect to find these 0.00 readings across the outer legs, do you mean in both directions (positive - negative and negative - positive) ?
Would that imply that each rectifier would show 0.0 twice, when measuring across all legs and in both directions ? I think (but I could be wrong) I had more than twice 0.00 for each rectifier.
I'll have to check but I think I have lots of positions on which it read 0.00 ohms.
When you're saying that I can expect to find these 0.00 readings across the outer legs, do you mean in both directions (positive - negative and negative - positive) ?
Would that imply that each rectifier would show 0.0 twice, when measuring across all legs and in both directions ? I think (but I could be wrong) I had more than twice 0.00 for each rectifier.
Hi Perry,
I desoldered the two FEP and two FEN rectifiers. Doing the ohms test then quickly revealed that one FEP was bad. I put in new, but lower rated 100 volt BT´s instead of 150 volt CT´s but that should be fine according to 1moreamp.
Instead of re-assembling Soundstreams when having worked on them, I power on the board while it´s upside down with the transistors pointing at the seiling. I have come to learn that one can do this for a short period of time without any problems.
On this board, U6 got pretty hot to the touch in a minute time.
My father thought there must be something wrong, but I told him that on the 705s it was also one or two of the U´s that got pretty hot, contrary to most other parts, so it must be normal, my guess is. I only have the 500s schematics, don´t know whether it´s exactly the same as a 500sx. Anyway U6 does show on the schematics. Do you think it´s normal this one gets hot faster than the rest ?
Anyway, thanks again as I think this board should be fine. It plays music properly.
There is however a very high frequency one can hear without any speakers connected. Pressing down (from topside) on one of the two large coils makes it stop.
What should we do there ?
Maybe pressing down on one of the coils of the Ref Picasso which I also heard making this sound in my car´s trunk will also make it stop ?
I desoldered the two FEP and two FEN rectifiers. Doing the ohms test then quickly revealed that one FEP was bad. I put in new, but lower rated 100 volt BT´s instead of 150 volt CT´s but that should be fine according to 1moreamp.
Instead of re-assembling Soundstreams when having worked on them, I power on the board while it´s upside down with the transistors pointing at the seiling. I have come to learn that one can do this for a short period of time without any problems.
On this board, U6 got pretty hot to the touch in a minute time.
My father thought there must be something wrong, but I told him that on the 705s it was also one or two of the U´s that got pretty hot, contrary to most other parts, so it must be normal, my guess is. I only have the 500s schematics, don´t know whether it´s exactly the same as a 500sx. Anyway U6 does show on the schematics. Do you think it´s normal this one gets hot faster than the rest ?
Anyway, thanks again as I think this board should be fine. It plays music properly.
There is however a very high frequency one can hear without any speakers connected. Pressing down (from topside) on one of the two large coils makes it stop.
What should we do there ?
Maybe pressing down on one of the coils of the Ref Picasso which I also heard making this sound in my car´s trunk will also make it stop ?
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