5687 filament question - Page 5 - 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 18th January 2003, 03:15 PM   #41
diyAudio Member
 
tone's Avatar
 
Join Date: Aug 2002
Location: Malaysia
Send a message via ICQ to tone
Default 5687

hi frank,
thanks for the prompt response..

Does this happen on both channels?
yes, both channel.i have tested all the resistor..tot it got burn or something..nothing wrong with the resistor..hmm...funny hey..

Are both sections of the tube // (looks like it from your diagram)?
yup, both section the same..should i put a grid resistor on the input? if so what value?

BTW: do u know how to convert an AR DAC1 to non-oversampling dac?..it uses yamaha YM3623B(Digital receiver) NPC SM5803APT(FILTER), ULTRAaNALOG 20 bit dac. any idea?
  Reply With Quote
Old 18th January 2003, 03:25 PM   #42
diyAudio Senior Member
 
fdegrove's Avatar
 
Join Date: Aug 2002
Location: Belgium
Default 5687

Hi,

What I don't understand is that it was fine before.

So,something must have thrown in the towel.

A gridresitor...about 1 Meg is the maximum you can put there but I doubt it will solve your problem though.

Here is what you can try: disconnect the cathode bypass cap and see if it behaves.

Something else to try is to disconnect the volume pot from the grid of the tube, just measure the voltage on the grid before and after disconnection.

What puzzles me most is that your circuit seems to work when you place the pot at the output.

Anyone with some simulator soft to help here?
Tones' circuit is on page 1.

Cheers,
__________________
Frank
  Reply With Quote
Old 21st January 2003, 11:32 AM   #43
diyAudio Member
 
Join Date: Nov 2002
Tone

Any progress on the preamp yet? Did you figure out the problem?
I am waiting to see what happens with yours because I would like to build one also and compare it to the 6SN7 linestage I just finished.


Joe
  Reply With Quote
Old 21st January 2003, 02:32 PM   #44
diyAudio Member
 
tone's Avatar
 
Join Date: Aug 2002
Location: Malaysia
Send a message via ICQ to tone
Default 5687 filament

hiyah burnedfingers:

should able to rectify what was wrong in couple of days..kinda busy this few days..sorry,..will keep u update ones i know the problem..see ya..

rgds,
tone
  Reply With Quote
Old 22nd January 2003, 02:07 PM   #45
diyAudio Member
 
tone's Avatar
 
Join Date: Aug 2002
Location: Malaysia
Send a message via ICQ to tone
Default 5687 is working again!!

hi frank,burnedfingers and all..

fix the problem! the problem was me myself!! wired the pot wrongly!!..idiot!! understand the right way... wired the other way!!
the preamp is working wonderfully..!!

burnedfingers:u can build it now!

sorry for the silly mistakes!!

thanks..

rgds
tone
  Reply With Quote
Old 22nd January 2003, 02:09 PM   #46
diyAudio Senior Member
 
fdegrove's Avatar
 
Join Date: Aug 2002
Location: Belgium
Default GOOD HEAVENS...

Hi,

That explains a lot of course.

I was just too afraid to suggest that.

Cheers,
__________________
Frank
  Reply With Quote
Old 22nd January 2003, 02:16 PM   #47
diyAudio Member
 
tone's Avatar
 
Join Date: Aug 2002
Location: Malaysia
Send a message via ICQ to tone
Default 5687

hi frank!

ha! ha! may god and u forgive me!..

thank you frank for ur help and advice..

i o u big time..!!

i would like to do something for u..do u need anything??..i have quite a range of precision opamp with me..want some>? or do u like to have some TDA1543 dac??..i can mail it to u for free..just a gift from me to u..mail me offline..tone_ne@hotmail.com

thanks

rgds,
tone
  Reply With Quote
Old 22nd January 2003, 02:20 PM   #48
diyAudio Senior Member
 
fdegrove's Avatar
 
Join Date: Aug 2002
Location: Belgium
Default i o u big time..!!

Hi Tone,

Very generous of you but thanks.

This is something all of us do for some reason or another,helping people out and seeing them succeed is the most rewarding return.

We're all happy to see you are,

Thanks again,
__________________
Frank
  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
Output trans plate load question 5687 vs 5965 phrarod Tubes / Valves 0 7th June 2009 02:24 AM
Aikido filament question Freecrowder Tubes / Valves 3 10th October 2008 12:38 AM
dht p-p filament question enochRoot Tubes / Valves 7 25th September 2005 04:31 PM
5687 filament heater question dr._sleep Tubes / Valves 2 25th August 2005 03:45 AM
Hum free 5687 AC filament supply, is it possable ? Shoog Tubes / Valves 17 13th January 2005 09:26 PM


New To Site? Need Help?

All times are GMT. The time now is 07:56 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