OS70/1750 datasheets - 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 7th December 2012, 07:48 PM   #1
diyAudio Member
 
chipie's Avatar
 
Join Date: Dec 2009
Default OS70/1750 datasheets

I'm searching for the data sheets of the Tungsram OS70/1750 tube. It's said they are equivalent with the 828 but I questioned that because filament of the OS70/1750 is rated at 7,5 Volt 2,5 Amperes (radiomeseum.org) while the 828 is rated at 10 V 3,25 A.
I searched the internet but could not find a data sheet for the Tungsram.
  Reply With Quote
Old 7th December 2012, 08:56 PM   #2
tricomp is offline tricomp  Denmark
diyAudio Member
 
Join Date: May 2004
Location: Jutland
FWIW,

This : http://frank.pocnet.net/short/054/4/441.pdf and the attached.

rgds,

/tri-comp

P.S.
You'll have to be able to understand a little Italian
Attached Files
File Type: pdf Vademecum P.H.Brans - 1953_(OS70-1750).pdf (599.6 KB, 33 views)
  Reply With Quote
Old 7th December 2012, 08:58 PM   #3
diyAudio Member
 
FullRangeMan's Avatar
 
Join Date: Aug 2009
Location: Brazil
Frank Tube datasheet database are offline now, nut you can search later:
http://www.mif.pg.gda.pl/homepages/frank/vs.html


OS70: http://frank.pocnet.net/short/054/4/441.pdf
__________________
>Never go to a psychiatrist, adopt a cat or dog from the streets. On the streets pets live only two years average.
  Reply With Quote
Old 7th December 2012, 09:14 PM   #4
diyAudio Member
 
FullRangeMan's Avatar
 
Join Date: Aug 2009
Location: Brazil
Frank is online again:

http://www.mif.pg.gda.pl/homepages/f.../049/8/828.pdf
__________________
>Never go to a psychiatrist, adopt a cat or dog from the streets. On the streets pets live only two years average.
  Reply With Quote
Old 7th December 2012, 10:37 PM   #5
tricomp is offline tricomp  Denmark
diyAudio Member
 
Join Date: May 2004
Location: Jutland
I promise you that you didn't see this before.
This is a page from the 1941, July issue of OZ, the Danish Magazine for Radioamateurs.
What is says about OS70/1750 is basically:

OS70/1750 is a modern universal Pentode for work as a modulator or TX tube until 4 meter (~70MHz) with a high efficiency.
2 tubes in Class AB1, Push-Pull yields 300W LF-output and by applying NFB the distortionfactor can be kept below 1%.

No curves, sorry

rgds,

/tri-comp
Attached Files
File Type: pdf Tungsram.pdf (634.0 KB, 23 views)
  Reply With Quote
Old 8th December 2012, 12:20 PM   #6
diyAudio Member
 
chipie's Avatar
 
Join Date: Dec 2009
Thx Tricomp, you also answered my next question for curves. Yes I'm planning to build a PP with those tubes. I would like triode connected but no triode curves to be found. So penthode connected is what is done in the schematics I saw till now ( STC 250 watt ) but I would like to do ultra-lineair with a 43% tap. BTW 300 Watt I don't need at all.
To get back on my original question, the OS70/1750 is equivalent with the 828 only filament is 7,5 V 2,5 A. Looks like Tungsram did a better job for getting the tube into emission than the RCA peepz.
Btw put the schematic with the post. It can be found at Dennis Grimwoods site Tubes
Attached Images
File Type: jpg STC250Aa.jpg (310.0 KB, 57 views)
  Reply With Quote
Old 16th December 2012, 11:58 AM   #7
tricomp is offline tricomp  Denmark
diyAudio Member
 
Join Date: May 2004
Location: Jutland
Data found in old Czechoslovakian tube manual (Russian language)
Please note filament-data!
Still no curves.

rgds,

tri-comp
Attached Files
File Type: pdf OS70-1750.pdf (38.0 KB, 29 views)
  Reply With Quote
Old 16th December 2012, 12:59 PM   #8
diyAudio Member
 
chipie's Avatar
 
Join Date: Dec 2009
Thx Tricomp, at least that clears out the filament question. So radiomuseum.org puts the wrong filament voltage and current.
For the 828 are some curves but not specifically for audio use, seems to me it will get an experimental project
  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
About repairing a 1750 watt power inverter gaetan8888 Power Supplies 23 6th September 2013 07:28 PM
sharp qa 1750 projection panel gollifer1 Parts 0 6th February 2004 06:25 PM


New To Site? Need Help?

All times are GMT. The time now is 06:16 AM.


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