Shine a bright light from the back of the board to confirm that there is no dark area between the pads.
If there is a ground plane or trace on the other side of the board, remove Q167 and R260 and confirm that the resistance between the pads is infinite (OL).
If there is a ground plane or trace on the other side of the board, remove Q167 and R260 and confirm that the resistance between the pads is infinite (OL).
On the pads for Q167
Drain to gate :OL
Drain to source: OL
Gate to source :7.25 M ohm
Replacing the cap didn’t change anything
Drain to gate :OL
Drain to source: OL
Gate to source :7.25 M ohm
Replacing the cap didn’t change anything
Between the pads for the caps the reading is in the mega ohms and when looking at the readings it seems like it’s charging another cap .
Did you try to look for a shadow with a bright back-light?
There may be contamination from electrolyte.
There may be contamination from electrolyte.
Amp will not produce audio with all parts installed .
I don’t have any MPS8099’s on hand to see if they are the fault .
Wondering can I use MPSA06’s in there place ?
I don’t have any MPS8099’s on hand to see if they are the fault .
Wondering can I use MPSA06’s in there place ?
Replaced Q174,187 with MPSA06 in place
Of the 8099’s.
All parts are installed and amp has output .
Will the 06’s survive in this amp or should I order the 8099’s
Of the 8099’s.
All parts are installed and amp has output .
Will the 06’s survive in this amp or should I order the 8099’s
Base and collectors are different MPS8099 vs MPSA06. Will need to twist-swap legs 2-3 on MPSA06.
I CANNOT confirm if MPSA06 can electrically replace MPS8099 but they do look similar on paper. If it's working then maybe?
I recommend if you DO buy MPS8099, to ALSO purchase MPS8599 - which is 8099's complement. Soundstream amps use both of these around muting and also auto-current circuits. I have a few of each 8099 and 8599 I could spare, but I dont have a lot. Hard to find I think.
I CANNOT confirm if MPSA06 can electrically replace MPS8099 but they do look similar on paper. If it's working then maybe?
I recommend if you DO buy MPS8099, to ALSO purchase MPS8599 - which is 8099's complement. Soundstream amps use both of these around muting and also auto-current circuits. I have a few of each 8099 and 8599 I could spare, but I dont have a lot. Hard to find I think.
Question on 2sa1304/c3296
Have A question. I have NOS of these A1304/C3296. The C3296-y have a hfe of 216, (all 15 of them). The A1304, they are green with a "T", they have an hfe of 160, six of them, and the rest have lower numbers. Using these in the Rubicon 1002, I was wondering if they will upset the bias as they are not equal?
I can get KSA940/KSC2073 from mouser which have the same specs.
Reason...Its been a few years (10+) and decided to get two of these going. The power supplies are good and I have NOS 2sa1302/c3281 that I'm going to install. The best matched sets. Front end boards are new from Lance, (X-Soundstreem employer) so those are good.
Do I have to worry about the hfe to help make it balanced?
Scott
Have A question. I have NOS of these A1304/C3296. The C3296-y have a hfe of 216, (all 15 of them). The A1304, they are green with a "T", they have an hfe of 160, six of them, and the rest have lower numbers. Using these in the Rubicon 1002, I was wondering if they will upset the bias as they are not equal?
I can get KSA940/KSC2073 from mouser which have the same specs.
Reason...Its been a few years (10+) and decided to get two of these going. The power supplies are good and I have NOS 2sa1302/c3281 that I'm going to install. The best matched sets. Front end boards are new from Lance, (X-Soundstreem employer) so those are good.
Do I have to worry about the hfe to help make it balanced?
Scott
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