SUMMIT AUDIO TLA100A schematic?

I'd guess a Norton amplifier (OTA). But it's just a guess.

:green: :green: :green:
lots of info ... lots of choices
:thumb:
hi fred
I got my 992 opamps

the LAB is good
it's all good

diy, diy
happy, happy
DIY

Hi Kev,

I'm glad you got the 992. Sorry it took so long! Looks like I'm probably going to be Oz for the month of November. Drop me an email and let's see if we can get together.

Cheers,

[quote author="buttachunk"] ...and we would still need to figure out what's in the compression cell.... a vactrol and some discrete stages ? (the input impedence is 1meg., and 100ohm trimpots for dc offset).[/quote]

Naa, a vactrol wouldn't need that sort of trimming. My best guess is a transistor-array type of VCA, more or less like the Valley:

http://www.gyraf.dk/schematics/VCAs_Ben_Duncan.pdf

Maybe the potting is just to get around Valley's patent?

:grin:

Jakob E.

I got a Summit Audio TLA-100A from a friend and it needs service, too. Can anybody give me advice where I can find the schematics since they don't appear in this thread ?

http://www.groupdiy.com/index.php?topic=45329.0

Mattias

Thanks a lot.

Could somebody send to me also the calibration procedure, and schematic of DCl-200.

Thanks 

rvperez said:

Could somebody send to me also the calibration procedure, and schematic of DCl-200.

Thanks 

Click to expand...

Summit will send it to you, but first you have to sign an NDA.

OlympicPhil said:

Hey, thanks everyone that's helped me, I've now got 3 copies of that schematic, 2 user manuals and 2 copies of the line-up procedures.

I'm blown away by the help I've received, so a huge thank you to everyone.

I've traced the problem back to two big black plastic blocks filled with hardened resin that looks as though they each contain a pair of caps and a pair of ICs (probably op-amps?).

Are these the Jensen 990s does anyone know?

Phil

P.S.  StDomingo, The B.Sc.(hons) is in Music Technology from Staffordshire University, Stafford site, class of 2001.

Click to expand...

Dear Phil, could you share a schematic copy of these TLA 100A please?
Thanks anticipated!
opacheco.

reply #25 has the link..

It's in the Tech Docs

..and that post is almost 14 years old..

If you look closer, User OlympicPhil hasn't been around since November 23, 2007, 01:49:31 PM

/Jakob E.

I had to put my TLA-100A into my technician recently to get it fixed, turns out the C-Cell was the cause of the problem. I ordered a new C-Cell & tube from Summit and they have now been replaced. My tech asked for an alignment procedure but noticed the one we have in the technical documents here was a bit different to my particular unit. He also mentioned this "I suspect that the Compression Cell is is based on an 1176 FET compression concept and so that makes the cal relatively simple. There does seem to be a symmetry trim and this is the last trim pot that I will touch. There is no meter Output Level trim, which is described in the alignment procedure but does not exist in this unit. It has a bias set up like a FET. It is technically a "voltage controlled amplifier" but based on a FET attenuation circuit like an 1176. If it was a VCA (the usual meaning) then first trim would be for symmetry and there would be no FET bias adjustment." Thought it could be relevant to the discussion here.