Psu 3 resistor values please.

[bob orbell]

A freind has asked me to look at his PSU 3, he thinks the voltages are too high, yes he has some crazy values in there, can someone please confurm the values, I do not have a CD, from memory I think they are R1 100 2W, R2 150K 2W, R3 22K 2W, R4 ?, R5 100 2W, R6?. thaks BOB. It's going to rain again tomorrow.

[Richard]

From memory?? wish I was that good

http://homepage.ntlworld.com/richard...DPSU3v3crt.pdf

[Greg.]

Hi Bob,

The values you quote are correct. Additionally R4 is 1K 2W and R6 is 15K 2W.

If you PM me your email, I'll forward to you a schematic.

Regards,

Greg

PS Arrr, Richard beat me to it!

[colin.hepburn]

Hi Bob/ Richard/Greg
Sorry don’t want the hi jack your thread
but I have this issue with my phono 2 Psu3 the pdf Richard posted is my update version as well running my phono 2 the voltage from it is high as well HT out is 283vHT the TX sec is 250v not 270v as in the pdf in Richards post I have used it like this for three year or more
PS The psu is only running the phono2

[Richard]

Hi Bob,

PSU voltages are for it fully loaded with Pre and Phono connected, has he got it set up like that? If not he just needs to check the voltage supplied at whichever of Pre or Phono he is using.

Hi Col,

Do you have the correct resistor fitted on the HT input for your Phono? If run from PSU without Pre attached it should be 10K. If run with Pre as well it should be 1K. Phono draws 4.6mA so the difference between those 2 input resistors would be 40V HT.

Like Bob's, the important place to check is the actual voltages in Pre and/or Phono as those loads will affect PSU.

[bob orbell]

Richard, Greg & Colin, thank you for the info. Greg, Richard has posted a CD for me, many thanks, and I do know that the PSU has to be loaded, my chum is using both PRE3 & PHONO3. Had a look inside yesterday and found R8 1k, R1 560, R4 100, R6 1k, apart from that it's fine. Thank's again all. BOB

[colin.hepburn]

Thanks Richard/Bob /Greg
When I built the psu2 I did not require to add R4 ZD1 C3 as I only use the phono it still has C4 installed and HT and Heater Diode were upgrade to fast recovery types
Resistors are as follows R1 100R R6 R15K
Is there any benefit of changing the Heater Rec from the 78S05 up to the LM1084 as I do not have any dropout problems with the 7805?
I have 283V HT when phono2 is connected Richard advised to change R6 10K which I will do
But what seems odd is both the psu2 and psu 3 schematics say the TX is 0-270v 60mA
My WAD TX is 0- 250v 60mA

[bob orbell]

Hi Colin and all, took a couple of photos of my PSU (WAD transformer in 3 case with 3 PCB) and my chums all 3 PSU, you can see the transformer is bigger in the 3, and the output voltage is more in the 3, I suppose it is because the series 3 is running 5 valves and a max. of 2 relays, as opposed to 4 valves only for the series 2. The pic. on the right is my chums and is under going upgrade. Hope this helps you Colin. Oh nearly forgot, I changed my reg. for the new type, before changing anything els and did notice a very small improvement. The reg. now live on the home made finned heat sink at the front. BOB