CJ PV-3 voltage values for schematic - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 6th February 2011, 06:39 PM   #1
arlekin is offline arlekin  Croatia
diyAudio Member
 
Join Date: Jan 2006
Location: Sibenik
Default CJ PV-3 voltage values for schematic

Hi, does anybody knows A/B voltage values for this schematic and transformer ratings?

I'm thinking about trying to build it without the phono stage.

Thanks

Click the image to open in full size.

Last edited by arlekin; 6th February 2011 at 06:43 PM.
  Reply With Quote
Old 6th February 2011, 06:59 PM   #2
llwhtt is offline llwhtt  United States
diyAudio Member
 
Join Date: Jun 2008
Location: SoCal
With just the schematic you can guesstimate the B+ by looking at the zener string (D6-13). Those are 33V zeners and there are eight in series for a total of 264 Volts. The B+ should be close to 264VDC.

Craig
  Reply With Quote
Old 6th February 2011, 07:24 PM   #3
arlekin is offline arlekin  Croatia
diyAudio Member
 
Join Date: Jan 2006
Location: Sibenik
Ok, thanks.

So, a transformer should give be something like 200V before Gretz?

Would 220V be too much?

Last edited by arlekin; 6th February 2011 at 07:27 PM.
  Reply With Quote
Old 6th February 2011, 07:50 PM   #4
llwhtt is offline llwhtt  United States
diyAudio Member
 
Join Date: Jun 2008
Location: SoCal
The raw supply needs to be higher than the regulator output. The regulator needs some extra voltage to work with but I am not sure how to figure how much extra. A 220VAC secondary will give you approx. 286 VDC, is that enough? I don't know without some research.

Craig
  Reply With Quote
Old 6th February 2011, 08:14 PM   #5
arlekin is offline arlekin  Croatia
diyAudio Member
 
Join Date: Jan 2006
Location: Sibenik
Ok, but wasn't that supposed to be 220VAC X 1.414 = 311VDC?
  Reply With Quote
Old 6th February 2011, 09:40 PM   #6
llwhtt is offline llwhtt  United States
diyAudio Member
 
Join Date: Jun 2008
Location: SoCal
If you use 1.3 as the x factor the voltages come out closer, always seems to work for me.

Craig
  Reply With Quote
Old 7th February 2011, 06:14 AM   #7
diyAudio Member
 
Join Date: Aug 2008
Location: Broomfield, CO
arlekin,

Here are voltage taken from my PV-3 referenced to your schematic;

Transformer secondary high voltage - 277vac
Transformer secondary low voltage - 11.86
Rectified DC (at top of C11) - 344vdc
B+1 (at top of R3) - 249.5vdc
B+2 (at top of R14) 248.2

Transformer does not have ratings marked on it but it does have the manufacturer and part number - Northlake Engineering, Antioch, IL, Part No. C126-112

I believe they are still in business but are now in Wisconsin.

You might try them if you need more info;
Northlake Engineering, Inc. > Exceeding Your Current Needs
  Reply With Quote
Old 7th February 2011, 11:45 AM   #8
arlekin is offline arlekin  Croatia
diyAudio Member
 
Join Date: Jan 2006
Location: Sibenik
Thank you both! You've helped me a great deal!

I guess that would be loaded?

I think I will go with back to back transformers. The first one 220VAC>15VAC, and the second one would be 12VAC>220VAC. That should give me about 275VAC.

Or maybe rather with a 220VAC>9VAC /12VAC>220VAC what should give about 293VAC. Just for safety because of the load.

I guess that the second secondary is just for the LED? Can be left out? Any other uses? Where is the heating?

I'm just not shure what power ratings for transformers should I use? Is 6VA too little?

Last edited by arlekin; 7th February 2011 at 12:04 PM.
  Reply With Quote
Old 7th February 2011, 01:04 PM   #9
arlekin is offline arlekin  Croatia
diyAudio Member
 
Join Date: Jan 2006
Location: Sibenik
Maybe a more reasonable question would be:

If I use back to back trafos would 15VA be enough or should I use 25VA?

I would like to save some space.
  Reply With Quote
Old 9th February 2011, 05:12 AM   #10
diyAudio Member
 
Join Date: Aug 2008
Location: Broomfield, CO
arlekin,

The measured voltages are in circuit (loaded).

The second secondary is for the filaments as well as the power LED. The crooked lines to the right of C17 represent the filaments.

I measured the actual resistance of R25 and the voltage drop across it & found the current at this point to be a little under 12ma.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
CJ PV-15 Pre sootshe Analog Line Level 6 8th February 2011 09:06 PM
Oscillating CJ PV-5 batsong Tubes / Valves 4 22nd April 2010 01:51 AM
UK Voltage CJ Walker CJ55 in the USA? Fingersfrank Analogue Source 4 5th April 2006 05:55 PM
Cap voltage values Yoda Solid State 4 6th September 2001 01:08 AM
help schematics for cj pv 10 dexter Tubes / Valves 8 19th July 2001 03:36 AM


New To Site? Need Help?

All times are GMT. The time now is 08:36 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2