• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

PSU for perusal

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Jump to Latest
philipbarrett

philipbarrett

Member
Joined 2005
Feel free to LOL! This is my 1st design which is really a hodgepodge of other people's work. Anyway, it's to power my EF86 based RIAA pre using some parts I already have.

Big Q, will it work? I had a tough time getting my head around the 6CA4 seperate heater/cathode thing.

Any & all input would be appreciated, forgive the pencil drawing but I haven't found a simple symbol program for my Mac (don't start-OK).

Thanks, Philip
 

Attachments

  • philips-riaa-pre.jpg
    philips-riaa-pre.jpg
    40.7 KB · Views: 170
philipbarrett

philipbarrett

Member
Joined 2005
OK that's the PSU post with the pre-amp schematic. Here's the preamp post with the PSU schematic just to keep everyoner on their toes!

Same questions, will it work? Will it eq per RIAA curve? Will you be able to read my chicken scratch?

How about using a single 20H/450ohm choke in the B+ (since I have one)?

Thanks in advance.

Philip
 
PRR

PRR

Member
Joined 2003
Paid Member
> Will it eq per RIAA curve?

Nope. I think it has the 2KHz-20KHZ drop, but no 500Hz-50Hz rise. See simulation below, ignoring pentode gain (about 40dB-46dB) but accounting for pentode plate impedance.

Output impedance is quite high, can't drive much/any cable. And you can probably eliminate the 470K resistor.

Pentodes have more noise than triodes. In phono amps, it could matter.

Otherwise it all looks fine.

How old are you? I thought I was the last guy to write "0.0033uFd". Kids today use those nano-things. At least I quit writing "3,300 uuFd" (micro-micro).
 

Attachments

  • philbart-pre-1.gif
    philbart-pre-1.gif
    18.7 KB · Views: 115
philipbarrett

philipbarrett

Member
Joined 2005
> Will it eq per RIAA curve?

How old are you? I thought I was the last guy to write "0.0033uFd". Kids today use those nano-things. At least I quit writing "3,300 uuFd" (micro-micro).
Click to expand...

OK here's the next revision. Check it out!

I'm actually 42 years young and I always stick with uF 'cos I'm pretty new to all this & it saves me confusion!

Thanks for the input.

Philip
 

Attachments

  • philips-riaa-pre-v2.gif
    philips-riaa-pre-v2.gif
    35.9 KB · Views: 96
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Top Bottom