Interest in PCBs for Bruno Putzey's Preamp and Hans Polak's relay volume control

[kempraj]

Thanks. Have replied to your PM.

 

[kempraj]

I have an extra set of : input selector board, one preamp board and one 16-step relay volume controller .

Sorry, I did write reply yesterday but was not posted. Thanks for you offer but I have now already ordered boards from Alexe’s website.

Thanks,
Kemp

 

[kempraj]

It is Grayhill 26ASD22-01-1-AJS.

Grayhill BCD encoder is currently out of stock everywhere and a lengthy lead time.

Can this alternative be used Grayhill 26AS22-01B16S

Thanks

 

[CentralCoast]

Any idea how much current the +12V and -12V rails draw on the preamp?

I have two pre amp boards. I am trying to decide to run them from silent switcher from diyaudiostore or from single pair of Hypex HPR12/HNR12

 

[alexcp]

If memory serves, it is about 70mA on each rail. Each of the four LM4562 needs about 10mA, plus each of the three relays needs about the same.

HxR12 modules are good for 100mA and up to 0.5W dissipation each, so perhaps two BPPBP boards would be too much for just one pair of HxR12s.

Jan Didden’s SilentSwitcher is good for 150mA, and apparently even more if you use a 9V source instead of 5V.

The current specs (150mA at the +/-15V and 0.5A at the 6/5/3.3V simultaneously) are such that they can be used with a standard 5V/2.1A USB charger. They are not actual limits; if you use a higher input voltage source like batteries (max 10VDC) or a wallwart delivering 9V at 2A, the available output currents are doubled.

Note that most USB chargers, even high power ones, provide less than 5V under load. I don’t know how this may affect the SilentSwitcher.

 

[CentralCoast]

Thanks

 

[tjencks]

Anyone try replacing LM4562 with LME49724 ?

Would it be possible ?

 

[alexcp]

LME49724 is a fully differential amplifier. It is not a drop-in replacement for LM4562.

 

[Ianmac]

Im a late comer to building a Bruno pre. I did have a board from the original free issue.Its up and running with a 10k linear pot and exhibiting all the issues with excessive gain. My Ncore amps auto shut down if the pot is over rotated with no input signal.
I need a 16 bit attenuator board and construction details.
Is there any chance anyone has one or can advise where I might get one ?

 

[alexcp]

I have a few 16-position (4-bit) boards left, but they are in the U.S. - shipping will be expensive. PM me if interested.

 

[sq225917]

If you over rotate the pot, input or not, it outputs dc. That's why you're ncores ate shutting down.

 

[Ianmac]

I have a few 16-position (4-bit) boards left, but they are in the U.S. - shipping will be expensive. PM me if interested.

Many thanks
PM sent

 

[ctpirn]

Can someone message member: alexcp and see if he can start a conversation with me about "I have a few 16-position (4-bit) boards left"
I like to get one.
Thanks!

 

[Mooly]

Can someone message member: alexcp and see if he can start a conversation with me about "I have a few 16-position (4-bit) boards left"
I like to get one.
Thanks!

Just put @alexcp and he will get the notification.

 

[ctpirn]

@alexcp do you still have 16-position (4-bit) boards left?
Thanks

 

[alexcp]

Sorry all those boards are gone.

 

[ElArte]

I would be interested in all of the above if 15 dB of gain is possible.

 

[ElArte]

Nevermind, didn’t realize it was a necro.