Neve VR meter calibration procedure

IN the process of recalibrating our neve consoles.

I Can't for the life of me find card PL11607 which is supposed to do the adjustments for the mutitrack meters. I have a few channels that are outputting +4Dbu but the meters are showing something else.

The documemtation from neve says to Adjust a few trim pots on card PL11607 to have the meters set up.

Is that a misprint? If so what card do I look for? If not where the hell is that card?
:?

Nevermind that was a misprint. I found it and more over it's global adjustment. Time to recap the meter bridge :wink:

ALL console plasma bargraph designs which I've ever seen use a master reference ramp to which the incoming switched signal level is referenced. -I saw this thread and thought that you were on the wrong track...

I think you still may be.

Having worked on lots of V-series meter bridges (V3's, V2's and VR's) I'd say that if you 're-cap' it out of caution you'll very posibly put in a LOT more faults than you fix.

-Can you answer me a quick question: -Have you swapped I/O modules to see if the problem is in the I/O module? -if not, DO THAT NEXT before pursuing any other line of thought regarding the meters.

The meter feed is switched from within the module and is buffered and the level set in there... (on the small fader module, I seem to recall) and given that the Neve small fader module is so awful in terms of capacitor lifespan, THAT'S where I'd start looking.

Swap I/O modules first, and don't even THINK about recapping the meterbridge until you're ABSOLUTELY certain that the fault can be no place else.

Keith

Keith
I got some 5-6 pages on how to calibrate a VR from the ground up. This was after our massive recapping jobs we have been doing. Finally got a couple of days to realign the boards closer to factory spec. If I did that procedure on a daily it would take me a couple of hours. But having only done it a few times, it takes much longer.


Anyway with the I/O modules swapped the problem stays with the meter. Had a conversation with a friend who was neve's tech out here and he suggested recapping the meter bridges. I was under the impression that it would be in the small fader module except for the fact that the group outputs will measure a proper 1K = +4Dbu = 1.228V = 0Vu but the meter will show something else.

My buddy says you should be able to tell based on frequency. If you are monitoring the buss output on your meters, test @ 1K with the cal switch on. You should be able to then test it @ say 100hz with the cal switch and the meters should read the same. If there is a big difference then recap the meter bridge if there is no difference or a slight difference then the problem is elsewhere.

yes, but... What the module outputs is NOT what goes to the meter. The signal passes through that annoying bus/tape/overdub switching logic, and is them buffered and sent back out to the meters.

If you've definitely swapped the module and had the problem stay with the meters then that does indeed seem to exonerate the module, but those meter blocks are a real bear to mess with, specially with those paper ribbons and that irritating "twelve-at-a-time" construction. (in groups of four and eight, which then merge to form twelve...)

Good luck with it, but SCOPE THE SIGNAL COMING IN on those blue ribbons te be ABSOLUTELY certain that the meters really are wrongly indicating, and not correctly indicating an incoming level discrepancy.

Keith

Yes they are a bugger to say the least.

Pucho812 is very probably correct Keith. Both Neve VR's at I dealt with at Whitfield Street Studios needed their meter cages recapped to sort out the shown level differences.
There are only a few caps that need to be changed per channel, but getting into then doing back up those cages is a pain in the ass!

Well,

I'm glad I gave those two VR's to Pucho! :wink:

:shudder:

Keith

[quote author="SSLtech"]Well,

I'm glad I gave those two VR's to Pucho! :wink:

:shudder:

Keith[/quote]

Keith if you ever dump your trash hear again you will hear from my lawers @
Dewey, Cheatem & Howe

..THey're no match for my lawyers either in the UK or here in the US...

In England I have retained the services of Sue, Grabbitt & Runn, and here in Florida I am served by Lowe, Downe & Fünké...

I also have a debt-recovery service run my a couple of 'friends'... "Crusher" and "Loblo"...

:twisted:

Keef