Neve 2254 build with ba185, ba191, ba192, ba283

[Spencerleehorton]

Hi end hiss is now the issue, going to wind a couple of 1:4 ratio txf for the side chain and will then test.

 

[Spencerleehorton]

Thought the side chain transformer could be causing the hiss issue but it’s not.
Will try and trace and see where the hiss is coming from, lots of mistakes on this channel already so expecting to find more!!

 

[Spencerleehorton]

Can’t seem to find the hiss now!!?
Ch2 not compressing now but good waveform? Seems it’s the 2n1711 which is faulty, will change and see what happens

 

[Spencerleehorton]

Couple of transistors blew on the ba191, replaced them and all up and running again!
Next step get the limiter working!!

 

[Spencerleehorton]

Nearly there with the limiter, it’s not doing much but I can definitely see it’s doing something.
Just need to get ch1 working the same now, should be able to record voltages on the ba192 and check the ch1 now as I think it’s the amp on the ba192 which has a fault and that’s why the waveform is all over the place!

 

[Spencerleehorton]

I can now see the limiter working on ch1 but I have blown something on the b185 pcb as needle is pinned on GR.
I suspect it’s the 2n1711 transistor, want to change this one anyways as I think this was my problem with weird waveform.

 

[Spencerleehorton]

Dodgy switch has sorted it, will test tomorrow and hopefully setup properly!!

 

[Spencerleehorton]

Ch1 still limiter not working?
Waveform is still not right, will hopefully find what it is soon!!

 

[Spencerleehorton]

Found 3 rogue resistors on the ba192 and tested it isolated and waveform fine, as soon as I then reattach I get dodgy waveform? Must be one of the other pcbs! Will go through them all again and try and find out why

 

[Spencerleehorton]

changed the 2m1711 and got more voltage out of D and E on B185, get 3v on ch2 which seems to limit quite well, on CH1 only get 1.3v so need to adjust this ideally.

 

[Spencerleehorton]

problem is definitely at the 2n1711, have ordered a new one but will also change the other transistors on the b185.
Will also look at F out on b283 as this is down on ch1 compared with ch2.
Ch2 does work well but there is a big difference in level when engaged but limit and compression is off, so do need to trace where the level jump is!

 

[Spencerleehorton]

after much faffing around, a cheaky blob of solder under neath a pcb was partly to blame, ive changed the PNP transistor on b185 for another bc214 and ive changed the 2n1711 again, limiting works now and the release time works on ch1, so im happy with ch1 now.
Ch2 the release time for the limiter doesnt work, its really slow, also a fair bit of noise and interference on ch2 so somethings not playing ball on there!!! trouble has been ive had to put right so many mistakes on ch1 i have to revisit ch2 now!!
At least im getting pretty well versed with this circuit now!!!

 

[Spencerleehorton]

ch2 limiter release wiper was the wrong way round, all works great now and the limiter does add what you need in my mind, well worth pulling my hair out to get to this point!!!

 

[EugeneKei]

Hey. Hope this thread is still alive. I have a question about Neve 22254 trafos. So maybe someone is able to help me with this.
According to schema 2254(mono unit) uses 3 trafos: input, interstage and output transformers. For output it uses L01166 and in our days we can use sowter 1717 or carnhill VTB1148. But what about the input and interstage transformers? What transformers we can use? I believe this info will be useful not just for me
Thanks

 

[Spencerleehorton]

Cheaper option is the OEP 2:1 A262A2E
Or Vigortronix VTX-101-002 PCB Audio Transformer 2:1 are only £17 each on eBay.

 

[EugeneKei]

Cheaper option is the OEP 2:1 A262A2E
Or Vigortronix VTX-101-002 PCB Audio Transformer 2:1 are only £17 each on eBay.

OEP 2:1 A262A2E on Aliexpress costs 120$ not the cheapest one to be honest))
Vigortronix VTX-101-002 is much more cheaper $41.26
What input and intestage trafos have you used? Or you have just output transformer(s) in your build?

 

[Rob Flinn]

OEP 2:1 A262A2E on Aliexpress costs 120$ not the cheapest one to be honest))
Vigortronix VTX-101-002 is much more cheaper $41.26
What input and intestage trafos have you used? Or you have just output transformer(s) in your build?

Not sure why you would want to buy British made transformers from ALIexpress.
https://uk.rs-online.com/web/p/audi...ShS3EE_Sqbapl_dnnv0aAihFEALw_wcB&gclsrc=aw.ds

 

[EugeneKei]

Not sure why you would want to buy British made transformers from ALIexpress.
https://uk.rs-online.com/web/p/audi...ShS3EE_Sqbapl_dnnv0aAihFEALw_wcB&gclsrc=aw.ds

Thank you Rob. So as I understood this one is an alternative for carnhill VTB1148, am I right? Carnhill is 200:600 and OEP 2:1 A262A2E is 150:600
But is it good alternative for 2254 output?

 

[Spencerleehorton]

carnhill VTB1148 good for output txf
The OEP and vigortronix are input and interstage, buy them from eBay way cheaper! ???

 

[Rob Flinn]

Thank you Rob. So as I understood this one is an alternative for carnhill VTB1148, am I right? Carnhill is 200:600 and OEP 2:1 A262A2E is 150:600
But is it good alternative for 2254 output?

I have no idea, I have only ever used Carnhill, Marinair & St Ives in Neve things I have built.