Mesa Mark 1 strange resistor lead

[diydidi]

Hi Guys.
I have a Mark 1 here for repair. From one of the 6L6's Pin3 there is a 220k resistor that has some length of wire attached to it. This wire is mildly wrapped around the screened input leads.
Never seen something like this before. Any ideas??
I have attached 2 pics.

[J M Fahey]

Am I going blind?

What wire are you referring to?

I see nothing unusual there.

Please edit pictures with small arrows pointing at it and describe colours,etc.

And when I see a wire which goes beyond the edge of the picture, I don't know where it goes so label everything you refer to.

[diydidi]

Sorry my bad!!

[Jazz P Bass]

Isn't that resistor a 2.2K grid resistor?

http://tubefreak.com/mb1pwr.gif

[diydidi]

No. This one is on pin 3 not 5.

[Jazz P Bass]

It would appear that they wanted to reference the overall shielding to B+.

Why?

Send Mesa an EMail & ask them.

[52 Bill]

It would appear that they wanted to reference the overall shielding to B+.

Why?

Send Mesa an EMail & ask them.

Gimmick cap to tame some sort of oscillation?

[J M Fahey]

Same here.

Mesa is known for adding (of course undocumented) gimmick caps here and there , apparentlyb to tame instability and oscillations.

Did I say "kludge kings"?

I bet they make a new prototype and instead of redoing from scratch many times (after all designing/developing a new model takes a long time, up to a year if you want perfect) they apply little band aids here and there until it works. Sort of.

[loudthud]

I worked on one of these that was still unsold for a Mesa dealer. The factory advised that you slide the loop back and forth along the coax to null noise and/or oscillation.

[The Dude]

I worked on one of these that was still unsold for a Mesa dealer. The factory advised that you slide the loop back and forth along the coax to null noise and/or oscillation.

I was going to like that post, but thought it might imply that I thought this was good build technique. IMO, just another in the long list of reasons I think Mesa is highly overrated.

[Jazz P Bass]

I was going to like that post, but thought it might imply that I thought this was good build technique. IMO, just another in the long list of reasons I think Mesa is highly overrated.

Ah, but think of the marketing angle.

"At Mesa, our amplifiers are custom tuned at the factory."

[Audiotexan]

Don't let me interrupt the hate fest, but PPPFFFFBFBBBFBFBFBBBTT!!!!!

Like Jim or Leo's techs never had to beat one into shape here or there...
Sheez
lol


PS: Yes I'll still stick up for the Mark series -at least up to III! lol
After that, anything after 86-87 is fair game IMO. *chuckles*

[The Dude]

'86,......is that when hot glue was invented?

[Justin Thomas]

If EL84s are the bitches of guitar amp design, Mesa's engineers sure seem to be the whipping boys... The amp above doesn't look NEARLY as bad as others I've seen; at least that "PCB" is roomy enough to put turrets etc. on if you blow it up... not likely to take out 10 other things if the traces short together. And admittedly, they sure crammed a lot of stuff in a little tiny box. I doubt I could do that to a Princeton. I do take issue with the amps with 15 knobs and a plethora of mini-switches... more moving parts = more stuff to break. And as I have said before, "sure, it sounds great, but don't call me when it blows up."

Justin

PS no hate for hacking up all those Princetons at the time - they weren't worth crap. Mesa now makes their own stuff; take a breath, we all know better now!

[J M Fahey]

Ah, but think of the marketing angle.

"At Mesa, our amplifiers are custom tuned at the factory."

So tell us what is your favorite local FM station and we'll tune your amp so between songs they provide suitable background music

Or you can keep up with Weather, latest News or favorite Sports while you play