should i dare wire/connect my vintage Neve 1272`s myself? or go to pro?

[ion]

okay... update time


i just got my 2x 1272 back from the tech.. he worked everythign out, i just have to house the PSU

but one problem occured... he was not able to figure out how to wire the TRIM pot correctly... he tried everything he could think of but the effect was always the same... insetead of a Volume fader function the pot only was functional as ON/OFF ..he tried many different ones..

API (if you can please chime in here) told me/us there would be a 10k resistor somewhere on the inner Connector and that the pot will have to be wired (inserted) between 2 connections where the resistor would be located.

fact is: THERE IS NO RESISTOR THERE

so my tech gave up on that issue and isnt available or next 2 weeks!

i need to know how to do this

 

[ion]

correction: the pot is not connected to the inner but to the rear connector


please hlpe out if you can

 

[API]

Ok, my first post in this thread.

First I must say that selling these 1272´s to Ion has been a rollercoaster ride!
Secondly, and I have told you this a few times now, please look at the schematic (from JLM) that I sent you, it is all explained in there how to hook up a trimmer.
The resistor should be 5.6k and it can either be located on the BA283 connector between pins P-L and ground where P and L are tied together.
Or pins P-L could have been brought out (with a wire) to the back connector and terminated to ground there with the 5.6k resistor.
I can not remember what resistor is in there now, it could be another value but if so just replace it.
If you want a 5db trimpot (trimming each gain step on the stepped switch) you insert a 5k Log pot with one side to pin P on the bA283 card and the other side to the 5.6k resistor with the wiper of the pot (middle connection) to pin L on the bA283 card.
This may or may not include hooking up some new wire from the BA283 card connector to the back connector and also re arranging the pins used on the back connector.

I hope this helps!

API

 

[ion]

"This may or may not include hooking up some new wire from the BA283 card connector to the back connector and also re arranging the pins used on the back connector."


is this the case only for the 5db stepped Trim (wich i dont need) OR will thi also be the case when wiring the usualy non stepped Trim???

if so i paid my tech now for nothing that i could even use since its all would to be re-wired???? man i am going crazy if that is the case  :'(


ok Dennis

PLEASE LOOK AT THE PICTURES I DID POST IN THIS THREAD EARLIER

i made pics of everything in there! WHERE is that 5.6 resistor????

the only thing that i know is that card-connectors P + L are brought out with a cable to the bac connector, yes

so what do i have to do now to get the potentiometer working man?

API i told you from start that i cant read shematics.. and if even the audio tech i gave them too didnt find out.. HOW CAN I ?

here are the pictures of the backside Amphenol connector ( the wiring around J,K,L is where the potentiometer is connected) her wired this according to Brent Averill.
it works despite the TRIM!
the other Picture is rom the inside of the back connector... i think that yellow isolation is new, so i think something has been done there as well..but i am not sure

i really need somebody to help me finish this and get the TRIM pot working or i fear i will give up on this soon

 

[Biasrocks]

i really need somebody to help me finish this and get the TRIM pot working or i fear i will give up on this soon

Good God, the drama!

Your problem is not with API, it's with Mr. Neve's design.

It's all there for you to understand, if you can't figure it out then take it to someone who can.

Brett Averill is a good one.

http://www.brentaverill.com/

Mark

 

[ion]

F.U.C.K.

 

[madriaanse]

but one problem occured... he was not able to figure out how to wire the TRIM pot correctly... he tried everything he could think of but the effect was always the same... insetead of a Volume fader function the pot only was functional as ON/OFF ..he tried many different ones..

Have you tried wiring the pot's wiper to "L"?

M.

 

[ion]

I didnt try anythign new yet

is that a serious advise with background knowledge?

i am sorry but i am not a native english speaker... what do you mean with the "wiper"?

and what "L" are you talking about now? inner connector? (there is allrady something on P+L)

and on the back connector the pot IS connected to J+K with some bridge to L and others... so

what do you mean?

 

[ultra-alex]

"... The potentiometer is a three legged animal having a fixed resistance between its outer legs. The middle leg functions like a wiper you can slide along its length. The wiper essentially splits the fixed resistor R1 in two resistors, R1A and R1B.  ..."

source http://www.ecircuitcenter.com/Circuits/pot1/pot1.htm

 

[ion]

i know its sad but i dont know what you guys tell me to do actually

should i deconnect the wire that my tech connected from the middle potentiometer leg to the rear connector and RE-connect it different or what yre you saying?

the middle wire from the potentiometer is the red one... it is now wire to "K" on the rear connector, but K and L are somehow connected to each other as you may see on the rear connector pic.

i dont get what you tell me to do

 

[madriaanse]

Here's how you connect it:
1. wiper (middle pin on pot) goes to pin L
2. outside pin (the one that measures 0 ohm to the wiper when trimmer is fully clockwise) goes to pin P
3. the other outside pin goes to ground (0V).

easy as 1-2-3

Pin K should go to a 1.5K resistor to a 100uF/25V electrolytic cap to ground. It shouldn't go anywhere else.

If the trimmer works in reverse just switch the two outside wires on the pot.

If that doesn't fix it I would simply recommend a couple of ice cold beers and some fresh air.

HTH,

M.

 

[ion]

thank you man but OH MY GOD!!!

so all the wiring by my tech wich i paid for was nonsense when the TRIM pot matters?

i mean.. look at the pic...(i hope we both speak about the added Amphenol backside conector that has been put on the rear of the module!!???)

the middle one (red) is connected to "K" + bridged to "L"

you said that one of the pot wires should go to "P" but my tech wired "P" to the XLR Output...

i did not test anything but he said it works all like this

so what should i do now? tear all he did down again and start again?

rather not.


madness  :-\

 

[drpat]

...

 

[ion]

hi

well i am in EU so sending it over to BAE is rather crazy

the tech worked on many BAE 1272 modules but ptobably not on vintage ones before now...

i apreciate your points and agree but all that is missing are a few little wires to get the TRIM pot working as such and not as on/off

i really cant imagine that this is such a difficult thing with all teh rest of the work is done... its like the last 5%

i dunno i think i made a mistake.. i maybe should have gone (or sell my vintage lot and do go) for the BAE reissue wich i can get for a good price

to be honest i dont have too much ambitions to go DIY... this stuff is really frustrating for me... instead of trial and error or several weeks and waiting waiting waiting, i could have used simply the BAE one and do some music....

i am seriously considering RE-selling my lot now to someone on here who can finish the last little potentiometer issue as neither me nor my tech seems to have a clue

i have haunted down 4 vintage neve knobs, the right faceplate color as spray can.... drilled and painted a faceplate, got the Amphenol connectors, had my tech wiring the amphenols to XLR Pigtails and PSU, recapped it... etc etc

so a lot of time and $ went into this allready

 

[[silent:arts]]

... to be honest i dont have too much ambitions to go DIY... this stuff is really frustrating for me... instead of trial and error or several weeks and waiting waiting waiting, i could have used simply the BAE one and do some music....

ion, with no offense:
this has been told you before.

... First I must say that selling these 1272´s to Ion has been a rollercoaster ride! ...

I think I know what you mean

 

[canidoit]

This is really sad 

Next time some newbie comes on this forum asking to see if any units are available for sale, people shouldn't bag them, especially from those that have been in the game of DIY for a while, who know that this is what can result!

I don't understand how people here can't relate to his frustration. Hes come in here asking an innocent question initially and now hes going to end up spending more money than he originally planned.

No joke mate, this is ridiculous.

 

[bluebird]

--

 

[drpat]

...

 

[madriaanse]

you said that one of the pot wires should go to "P" but my tech wired "P" to the XLR Output...

i did not test anything but he said it works all like this

so what should i do now? tear all he did down again and start again?

rather not.


madness  :-\

Whoa, slap that tech. The only thing going to the XLR output should be pin 5 and 8 of the LO1166 transformer. I would demand a refund and find another tech to help you out.

M.

 

[MagnetoSound]

I think that a lot of confusion is arising from ion not always being clear about which of the two Amphenol connectors is being referred to - the B183/283 card connector or the rear connector on the back of the module.

The XLR output should be connected to R and T on the rear connector, which should be fed from the output secondary.

The trimmer goes between P and L on the card connector, with the wiper to pin L - normally via linked pins K and L on the rear connector. (This breakout to/from pins K and L on the rear connector is to enable an external fader to be connected, if desired, after the trimmer. Unnecessary confusion, I know, but worth explaining.)

I hope this picture of the original schematic helps a bit.

You guys are right, this has all been much more trouble than it should have been.