hello🙂
i wonder if anyone use or know this amp.
i need its schematic to set the bias correctly..one of the amps warms 3 deg more then the other and i want to fix it.
i will really appreciates any help.
good day
David.
i wonder if anyone use or know this amp.
i need its schematic to set the bias correctly..one of the amps warms 3 deg more then the other and i want to fix it.
i will really appreciates any help.
good day
David.
If setting the bias is all, you don't need a scematic. Just turn the bias pot so that the outputs are in cuttoff, then measure the voltage across the emitter resistor, 0.1-0.5Ohms. tweak the pot until you see voltage begen to develope accross the resistor. This is where you want to bias. Disconnect one of the output collectors, and insert an ammeter to be sure.
Re: stage accompany pps-1200 amp
Do you think this is a problem? I wouldn't bother to mess with it.
Do you think this is a problem? I wouldn't bother to mess with it.
thank you both
yes. i think that is the problem.
i didnt see a bias pot thats why i want the schematic..
have a great day!🙂
yes. i think that is the problem.
i didnt see a bias pot thats why i want the schematic..
have a great day!🙂
Anyone got a schematic for Stage Accompany power amp? This is an older unit, blue casing, 2 toroid power transformer, has 16 pair of 2SC5200 per channel. Blown up, some resistors are burnt.
lumanauw said:
I suspect the bias is set using set resistor values after they had a pot in the prototype.
I wouldnt bother for 3 degrees either unless the 3 degrees is 3 degrees above 120 degrees C !
It will be quite a bit of hassle to set the bias plus you might make a mistake and blow the output transistors.
Is it really worth the hassle ?
The last time I set up a bias I blew 6 MOSFETS and it cost me around £15 to replace them.......
My problem is different than dud_wity 's (thread starter).
I wanted to repair a blown SA power amp due to overdrive (not the bias problem).
Anybody got SA schematic or service manual?
I wanted to repair a blown SA power amp due to overdrive (not the bias problem).
Anybody got SA schematic or service manual?
Hello David,
The complete PPA 1200 service manual is on his way to me.
I will place it on my site as soon as possible:
www.sa-vintage.com
Also this week on my site:
- Service Manual PPE 2410
- Service Manual Sa 1600/800
- User Manual ES20
- PlexiGlas SA Blue Box foto's from the showroom in Hoorn
- and over 60 scans of SA Product Information
Greetz Webbie...
The complete PPA 1200 service manual is on his way to me.
I will place it on my site as soon as possible:
www.sa-vintage.com
Also this week on my site:
- Service Manual PPE 2410
- Service Manual Sa 1600/800
- User Manual ES20
- PlexiGlas SA Blue Box foto's from the showroom in Hoorn
- and over 60 scans of SA Product Information
Greetz Webbie...
Hello,
Quoted from my site, mite be a help for you all if want to buy this beautifull apparatus:
The PPA 1200 is the best amplifier SA has ever built.
One of the nicest things of the PPA is the build in crossovers.
The presets in the PPA 1200 have been coupled to electronic internal crossovers.
It’s even possible to develop your own crossover with the existing soft and hardware.
Unfortunately at present time an amplifier with a capacity of 600W RMS in 4 ohm and a weight of 36kg is no longer suitable for PA use.
The use of large number of electronic components, from which the amplifier is build, is also no longer profitable.
Buying second hand:
If you want to buy a second hand PPA 1200, it’s best to look at a PPA with a serial number higher than 271 (last four digits of the serial number).
It has interchangeable crossovers. On the outside the unit is recognizable from the “Input Link” at the back of the amplifier.
PPAs with a serial number less then 272 do not have an “Input Link” and also doesn’t have interchangeable crossovers.
The PPAs (with serial number higher then 271) have got many advantages in contrast to the first series with the lower serial numbers:
- thicker power cord
- interchangeable crossovers
- 12V relays, instead of 6V relays
- improved 5V power supply
- no annoying audible 50Hz hum anymore
- much better reliability of service
- better serviceable
Greetz Webbie...
Quoted from my site, mite be a help for you all if want to buy this beautifull apparatus:
The PPA 1200 is the best amplifier SA has ever built.
One of the nicest things of the PPA is the build in crossovers.
The presets in the PPA 1200 have been coupled to electronic internal crossovers.
It’s even possible to develop your own crossover with the existing soft and hardware.
Unfortunately at present time an amplifier with a capacity of 600W RMS in 4 ohm and a weight of 36kg is no longer suitable for PA use.
The use of large number of electronic components, from which the amplifier is build, is also no longer profitable.
Buying second hand:
If you want to buy a second hand PPA 1200, it’s best to look at a PPA with a serial number higher than 271 (last four digits of the serial number).
It has interchangeable crossovers. On the outside the unit is recognizable from the “Input Link” at the back of the amplifier.
PPAs with a serial number less then 272 do not have an “Input Link” and also doesn’t have interchangeable crossovers.
The PPAs (with serial number higher then 271) have got many advantages in contrast to the first series with the lower serial numbers:
- thicker power cord
- interchangeable crossovers
- 12V relays, instead of 6V relays
- improved 5V power supply
- no annoying audible 50Hz hum anymore
- much better reliability of service
- better serviceable
Greetz Webbie...
Hello,
Finally found the complete service manual of the PPA 1200 in PDF format.
About a few days the service manual will be aded to my site, if I solved my disk space problem (less the 4mB available).
The service manual is 7mB.
When someone is in a hurry I can mail the service manual.
David you got mail 🙂
Greetz Webbie...
Finally found the complete service manual of the PPA 1200 in PDF format.
About a few days the service manual will be aded to my site, if I solved my disk space problem (less the 4mB available).
The service manual is 7mB.
When someone is in a hurry I can mail the service manual.
David you got mail 🙂
Greetz Webbie...
Hello,
Maybe one of the moderators can change the topic title.
The title is not correct.
"stage accompany pps-1200 amp"
Should be:
"stage accompany ppa-1200 amp"
Greetz Webbie...
Maybe one of the moderators can change the topic title.
The title is not correct.
"stage accompany pps-1200 amp"
Should be:
"stage accompany ppa-1200 amp"
Greetz Webbie...
- Status
- Not open for further replies.