80's Technics Integrated Amps
- Thread starter GreenV
- Start date
So, I put the 2004 B in the V4X, replacing the BC someone had substituted previously. It looks like all they did was replace the module, one pre-driver with a MCM part, and re-solder the hot-spots on the board. They messed up the solder pad on pin 16 so I had to fix that...and replaced the A1123 and C2631 parts with matched pairs of A1013 and C2383. That was all the amp needed! Back to great sound again! On to replacing the broken speaker output jacks, to finish up.
Thanks to you again, for all your valuable info and guidance!
Thanks to you again, for all your valuable info and guidance!
Indeed, this amp had broken terminals on three, so testing was done on one channel with an alligator extension from the inside to the speaker wire.
I have developed a way to replace the whole SJF-4815 block by removing it and using a piece of press-board in it's place. I center dual
5-way binding posts (Mueller BU-P6883) in the openings in the back panel, drill holes in the press-board for the terminals and mounting screws to go through, and solder wires from each down to the circuit board. Then I can use any set of speaker wires to the amp...including dual banana plugs (Pomona MDP-4898 series) for quick connection.
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Emiliano974
New Member
Buonasera, questi due ragazzi qua sotto li ho recuperati nel cassone dei rifiuti Rae, li ho presi senza speranza, ed invece oltre che funzionanti, belli come solo una volta sapevano fare, dopo una soffiata e qualche spruzzata di disossidante ora suonano, e bene. Mai conosciuto amplificazioni Technics, l'SU-V3 mi ha sorpreso, bel suono, anche con difficili diffusori Chario Hiper 1 + Hiper Sub si è ben comportato. L'altro, SU-V660, nonostante la mia riluttanza, mai provata ma solo letta in ogni dove si parli di amplificazioni, presenza di modulo finale STK o SVI come c'è scritto non sò s siano la stessa cosa, anche lui ha sorpreso per qualità sonora.
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Hi everyone, looking for info around the SU X901 and SU X980D
I have recently lost to repairs, SU X9600 Would love to know what I have running my 79 Sansui and any reviews people have of this SU X9 Range
And which I should have as No1, I have views myself but would love to hear what you guys think.
I have recently lost to repairs, SU X9600 Would love to know what I have running my 79 Sansui and any reviews people have of this SU X9 Range
And which I should have as No1, I have views myself but would love to hear what you guys think.
You could probably download the service manuals for both and see if those parts are the same in the parts list. I have owned both of them but have no idea if they are the same size or not. Maybe they are...Hello all...
Does anyone knows if a spare SU-V4 volume knob would fit on a SU-V6 (that miss that volume knob, you understood...) ?
View attachment 3437642
Thank you for your advise, but I already did it and they seem not to be exactly the same (well... the manuals are not cristal clear...)
The as you can see in the picture, the SU-V6 knob "slot" goes all the way
Xenon-Codex
Active Member
What are the specs for the knob?
If only I had it... I just have the reference thanks to the service manual
Hello to all. I need some help please. I think @SVI2004A can help me on this from what i saw and what i've read in the thread.
I have 2 Technics A1000MK2. Suddenly one of them a lot of months back died completely. No lights. No standby nothing. in the past i've noticed FLICKERING of the standby led.
Sometimes the amp did not power on. Another example when i was pulling out the power plug and insert the plug again sometimes it worked. After that dead completely.
I switched the power supplies from the other amp i have but nothing. I changed the speaker bridges nothing again.
You think this might be a resistor or capacitor issue on the main PCB ? Or the SVI chips need to be replaced ? It might be another IC on the board ?
IF the problem is SVI switching to SVI3206 from 3205B means lower music wattage output or the same as the system was originally designed when the volume is in the same position ?
I don't want to throw it away. I've never used them above 11 o 'clock.
Other problem is the EQ90 equalizer. The screen is flickering sometimes fades in or out or the dot matrix is waving ( i mean when it lits). Here i suspect capacitors but i'm not sure.
Thanks in advance.
I have 2 Technics A1000MK2. Suddenly one of them a lot of months back died completely. No lights. No standby nothing. in the past i've noticed FLICKERING of the standby led.
Sometimes the amp did not power on. Another example when i was pulling out the power plug and insert the plug again sometimes it worked. After that dead completely.
I switched the power supplies from the other amp i have but nothing. I changed the speaker bridges nothing again.
You think this might be a resistor or capacitor issue on the main PCB ? Or the SVI chips need to be replaced ? It might be another IC on the board ?
IF the problem is SVI switching to SVI3206 from 3205B means lower music wattage output or the same as the system was originally designed when the volume is in the same position ?
I don't want to throw it away. I've never used them above 11 o 'clock.
Other problem is the EQ90 equalizer. The screen is flickering sometimes fades in or out or the dot matrix is waving ( i mean when it lits). Here i suspect capacitors but i'm not sure.
Thanks in advance.
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SVI2004A
Synchro Bias
This set has 2 xfmrs
big one T1 - main xfmr… this is controlled by a relay (RL701) that is controlled by standby circuit.
the small one (T701) - when amplifier is plugged in, this should always have AC 12.5V coming out
so I’d check if the 12.5V ac is coming out of T701
then check if RL701 - does it click when front power switch is operated…. If yes.. check fuse F1, relay contacts or dry joints… possibly on relay
if no we will look into power switch circuit
big one T1 - main xfmr… this is controlled by a relay (RL701) that is controlled by standby circuit.
the small one (T701) - when amplifier is plugged in, this should always have AC 12.5V coming out
so I’d check if the 12.5V ac is coming out of T701
then check if RL701 - does it click when front power switch is operated…. If yes.. check fuse F1, relay contacts or dry joints… possibly on relay
if no we will look into power switch circuit
Power supplies on the multimeter, the values ARE all OK. Normal voltage. A small capacitor on the pcb of the small power supply changed also. Nothing.
Do you suggest to buy first the relays ? and replace them ?
NO click at all. No power led activity at all. Even if i plug several times the power cable and put it back. Even if i press the switch.
With multimeter ? Or to replace something directly ?
