SSlmixed.com Forum

Tech discussion => 4K,6K,8K Series => Topic started by: Megaphon on March 01, 2020, 07:41:31 PM

Title: Trim pot identification
Post by: Megaphon on March 01, 2020, 07:41:31 PM

Hi!

On the G channel motherboards there’s a trim pot labeled “L.TRIM”, located just below the group matrix. I can’t find it in any schematics. Anyone here who knows what it’s for?

/Ulf

Title: Re: Trim pot identification
Post by: Megaphon on March 03, 2020, 09:57:56 AM

After studying also the E-series schematics I’ve now found that this pot is only in cirquit together with the 241 channel amp. Since my consoles are G+ and have the 291 channel amps this trim pot is doing nothing at all.

/Ulf

Title: Re: Trim pot identification
Post by: amillar on March 03, 2020, 09:28:15 PM

And it's also for the the '01, but not the '149. On the '291 I put the "0dB" trim pot on the board instead, there was no way with the new circuit arrangement that we could use the trim pot on the '611.

On the '01 and '241 you adjust it for 0db with the gain pot in the centre position.

I'm now trying to remember what the heck the '241 actually was...I haven't got a circuit for that either! (hint, hint...) I seem to remember it has a transformer on it??? I'm pretty sure it was a 1986ish Trevor Stride design (like the '242 EQ was).

Cheers,

Andy

 

Title: Re: Trim pot identification
Post by: Chris Simon on March 03, 2020, 10:21:29 PM

It does in fact have a transformer.

Title: Re: Trim pot identification
Post by: amillar on March 04, 2020, 06:27:28 PM

Many thanks Chris - yes I thought 1984 and typed 1986!

Took me a while to spot the difference, the 241 has 4db more headroom on the line input than the 01