Looking for informations on Marconi TF2331 Distortion Factor Analyser - 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 24th November 2006, 01:06 PM   #1
bembel is offline bembel  Europe
diyAudio Member
 
bembel's Avatar
 
Join Date: Aug 2006
Send a message via Yahoo to bembel
Default Looking for informations on Marconi TF2331 Distortion Factor Analyser

Hi all,
I found a Marconi TF2331 Distortion Factor Analyser that need to be fixed, I googled and found nothing (free).
Any documentation is welcome (Schematic, Op Manual, block diagram, detailled spec or calibrating procedure.)

Thanks
__________________
Plus je pédale moins vite, moins j'avance plus vite !
  Reply With Quote
Old 26th November 2006, 12:28 PM   #2
bembel is offline bembel  Europe
diyAudio Member
 
bembel's Avatar
 
Join Date: Aug 2006
Send a message via Yahoo to bembel
Hey englishmen, where are you ?
Nobody ever used this one ?
__________________
Plus je pédale moins vite, moins j'avance plus vite !
  Reply With Quote
Old 26th November 2006, 01:11 PM   #3
EC8010 is offline EC8010  United Kingdom
diyAudio Moderator Emeritus
 
EC8010's Avatar
 
Join Date: Jan 2003
Location: Near London. UK
I scrapped one about fifteen years ago, but didn't keep the manual...
__________________
The loudspeaker: The only commercial Hi-Fi item where a disproportionate part of the budget isn't spent on the box. And the one where it would make a difference...
  Reply With Quote
Old 26th November 2006, 01:24 PM   #4
bembel is offline bembel  Europe
diyAudio Member
 
bembel's Avatar
 
Join Date: Aug 2006
Send a message via Yahoo to bembel
did you use it ?
Thanks
__________________
Plus je pédale moins vite, moins j'avance plus vite !
  Reply With Quote
Old 26th November 2006, 01:31 PM   #5
EC8010 is offline EC8010  United Kingdom
diyAudio Moderator Emeritus
 
EC8010's Avatar
 
Join Date: Jan 2003
Location: Near London. UK
No. As far as I remember (this was a while ago), you had to manually tune to null the fundamental, then you could measure how much distortion was left. I think it was good down to 0.01% or -80dB. Shortly after acquiring the Marconi I bought a much better test set for £40 + VAT that automatically nulled the fundamental and did a host of other things as well, hence the scrapping of the Marconi.
__________________
The loudspeaker: The only commercial Hi-Fi item where a disproportionate part of the budget isn't spent on the box. And the one where it would make a difference...
  Reply With Quote
Old 26th November 2006, 01:38 PM   #6
bembel is offline bembel  Europe
diyAudio Member
 
bembel's Avatar
 
Join Date: Aug 2006
Send a message via Yahoo to bembel
Thanks EC8010, Could you confirm that the only internal oscillator is for calibration purpose. ---> So no an ext. gen. must be used ?
And that the output bananas are the distortion results (fundamental substracted) intented for oscilloscope display ? 1M outputZ ?
__________________
Plus je pédale moins vite, moins j'avance plus vite !
  Reply With Quote
Old 26th November 2006, 01:48 PM   #7
EC8010 is offline EC8010  United Kingdom
diyAudio Moderator Emeritus
 
EC8010's Avatar
 
Join Date: Jan 2003
Location: Near London. UK
I can't remember about the internal oscillator, but if you try measuring its distortion, you'll soon find out if it's any use. Linear Technology (IC manufacturer) had some application notes with circuits for low distortion oscillators. For valves, you probably only really want 1kHz (general THD test), 30Hz (finds output transformer problems), and 10kHz (finds driver slewing problems etc). The monitor output will be fine going into the standard 1M input resistance of an oscilloscope and I thoroughly recommend that you use it - the shape of the distortion waveform tells you an awful lot about what caused the distortion.
__________________
The loudspeaker: The only commercial Hi-Fi item where a disproportionate part of the budget isn't spent on the box. And the one where it would make a difference...
  Reply With Quote
Old 26th November 2006, 01:59 PM   #8
bembel is offline bembel  Europe
diyAudio Member
 
bembel's Avatar
 
Join Date: Aug 2006
Send a message via Yahoo to bembel
Thanks a lot EC8010, I will recieve this Marconi unit soon, and your answers permit me to debug some contradictions the sender told me.
Thanks again.
__________________
Plus je pédale moins vite, moins j'avance plus vite !
  Reply With Quote
Old 26th November 2006, 02:06 PM   #9
EC8010 is offline EC8010  United Kingdom
diyAudio Moderator Emeritus
 
EC8010's Avatar
 
Join Date: Jan 2003
Location: Near London. UK
You're welcome, but please remember that I'm going from memory of something fifteen years ago - I could easily be wrong.
__________________
The loudspeaker: The only commercial Hi-Fi item where a disproportionate part of the budget isn't spent on the box. And the one where it would make a difference...
  Reply With Quote
Old 27th November 2006, 12:28 PM   #10
bembel is offline bembel  Europe
diyAudio Member
 
bembel's Avatar
 
Join Date: Aug 2006
Send a message via Yahoo to bembel
Your input is very appreciated anyway EC8010 ! (even an unsure one from memory is still better than no-one at all).

To close the subject I forgot to say that I wonder what use have this "supply" pot ? here's a picture attached (this is the right-upper most pot).
Any idea?
I wonder also if in the "Cal mode" you need to loop I/O or if it is internally done (any memory of this ?).

thanks again.

PS: still looking for Schem/doc/manual.
Attached Images
File Type: jpg tf2331.jpg (94.9 KB, 79 views)
__________________
Plus je pédale moins vite, moins j'avance plus vite !
  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
Distortion analyser circuit steevo Solid State 12 21st July 2008 01:42 AM
IM Distortion Analyser Alain Dupont Parts 2 6th January 2005 02:48 AM
Usable distortion analyser for Pre-/Amps MichaelB Solid State 22 1st February 2004 12:39 PM
HP334A Distortion Analyser Netlist Swap Meet 1 14th October 2003 10:33 PM
HP333A Distortion Analyser Netlist Equipment & Tools 12 13th October 2003 09:40 PM


New To Site? Need Help?

All times are GMT. The time now is 03:27 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