Search found 15 matches

by stratele52
Sat Feb 23, 2013 9:17 am
Forum: Dual Caliber
Topic: Caliber .50 + ; Pots needed
Replies: 2
Views: 1241

Caliber .50 + ; Pots needed

I'm looking for 2 pots for Mesa Boogie Head , .50 caliber + These pots are for Presence and for Reverb . Customer broke the shafts Can't find these pots on the web. I just find one place in United State but they don't ship in Canada. Can you help me ? Thank's amprepairparts.com/pots.htm : they don't...
by stratele52
Thu Mar 17, 2011 5:01 am
Forum: Dual Caliber
Topic: .50 Caliber + Question
Replies: 3
Views: 1099

Re: .50 Caliber + Question

If you turn the volume and the hum is louder; this is not a filter caps problem. Filter caps problem give the same amout of hum at "0" volume or at max volume. You said you check the tube. how do you do that ? put new tubes in or use tubes tester ? What I suggest you should do; Remove the first prea...
by stratele52
Sat Mar 05, 2011 5:20 pm
Forum: Rectifier Series
Topic: How to install a bias pot in a Rectifier
Replies: 109
Views: 100739

Re: How to install a bias pot in a Rectifier

It's a nice probe but you can only test the Kathode current ( milliamps or millivolts) . You should be able to mesure Plate voltage ( 400 volts) to know if your bias is ok ( Kathode current).

With a probe made by Amp-Head.com. you can do those two mesurements safely
by stratele52
Sun Jan 23, 2011 3:02 pm
Forum: Rectifier Series
Topic: How to install a bias pot in a Rectifier
Replies: 109
Views: 100739

Re: How to install a bias pot in a Rectifier

I look at Mouser:

Bourns have some at $2 - $3 each too, I don't take time to check if they made 24 K ohms for those model

The name on mine are Elecsound, Trimmer, BI and I have some Bourns and some Alen Bradley buy at a surplus store.
by stratele52
Sun Jan 23, 2011 4:19 am
Forum: Rectifier Series
Topic: How to install a bias pot in a Rectifier
Replies: 109
Views: 100739

Re: How to install a bias pot in a Rectifier

I don't know where you see cernet multitour pots are expensive ? My local electronic store sell them $1.99 Canadian.

And I do lot of bias mod with them.
Multitour are easyer to adjust, to fine tune and won't move by itself. And I read they are more DC volt "resistant"
by stratele52
Tue Nov 02, 2010 4:41 am
Forum: F Series
Topic: Possibly sell F50, but there's a problem
Replies: 4
Views: 1570

Re: Possibly sell F50, but there's a problem

I'll try to spray some contact cleaner on the switch, Spray around the switch schaft, if you have no acces hole for switch contact.

The contact cleaner will go inside the swich and could fix it.
by stratele52
Thu Oct 28, 2010 4:18 pm
Forum: Rectifier Series
Topic: 4 Power Tubes in a 3 channel triple Rec?
Replies: 18
Views: 1131

Re: 4 Power Tubes in a 3 channel triple Rec?

Mark IV you are RIGHT.

I'm sorry, my excuse is I'm french speaking and some time I make mistake for translating english in french and to understand what people write. And this subject " ..plug to 4 ohms jack a 8 ohms speaker" is not easy .

Very sorry because you look to know a lot on amps
by stratele52
Thu Oct 28, 2010 5:12 am
Forum: Rectifier Series
Topic: 4 Power Tubes in a 3 channel triple Rec?
Replies: 18
Views: 1131

Re: 4 Power Tubes in a 3 channel triple Rec?

I hope this will help: Removing tubes / output impedance Tube Guitar Amplifiers Essential, by Gerald Weber, page 213 ......When you remove two of the output tubes, the primary must be doubled to accommodate de two remaining output tubes. An easy way to do this is to use a speaker load that is twice ...
by stratele52
Wed Oct 27, 2010 6:46 am
Forum: Rectifier Series
Topic: 4 Power Tubes in a 3 channel triple Rec?
Replies: 18
Views: 1131

Re: 4 Power Tubes in a 3 channel triple Rec?

NO NOT 4 OHMS , but 16 ohms

Removing tubes give higher impedance ( ohms) on the primary of your transformer so you have to plug secondary to higher ohms speakers
by stratele52
Tue Oct 26, 2010 9:06 am
Forum: Rectifier Series
Topic: How to install a bias pot in a Rectifier
Replies: 109
Views: 100739

Re: How to install a bias pot in a Rectifier

By switching to EL34 bias you won't use EL34 voltage for your 6L6, but you change current flow in tubes, by changing negative apply to 6L6's grids. This is more dangerous. More current will flow in tubes and could destroy it. If you want more voltage on your 6L6's, Use the Bold/Sponge swith to Bold,...
by stratele52
Tue Oct 26, 2010 7:44 am
Forum: Rectifier Series
Topic: How to install a bias pot in a Rectifier
Replies: 109
Views: 100739

Re: How to install a bias pot in a Rectifier

shatteredsquare, No you can't do that, you will damaged your 6L6 if you flip the bias switch from 6L6 to EL34. You won't have a EL34 sound if that's what you hope The only difference in this bias switch ( if you flip to EL34) is to give a hotter bias to power tubes. EL34 need a hot bias. I can't tel...
by stratele52
Tue Oct 26, 2010 3:58 am
Forum: Rectifier Series
Topic: How to install a bias pot in a Rectifier
Replies: 109
Views: 100739

Re: How to install a bias pot in a Rectifier

You are right about bias and that is I have done, but in all other switches position (lower voltage) the bias are very cold. Too bad, this is Mesa Boogie with all their gadgets !!! Thank's for everything. For your information mickey this is the sketch of my new two pots bias circuit in the low half ...
by stratele52
Mon Oct 25, 2010 3:31 am
Forum: Rectifier Series
Topic: How to install a bias pot in a Rectifier
Replies: 109
Views: 100739

Re: How to install a bias pot in a Rectifier

Thank you very much for the quick response mickey383. It is exactly what I believe and this is the way to the bias that I did. I am very disappointed with the way Mesa Boogie built this amp . There are too many compromises with regard to the bias. http://i21.servimg.com/u/f21/14/01/45/41/dscn2413.jp...
by stratele52
Sun Oct 24, 2010 2:30 pm
Forum: Rectifier Series
Topic: How to install a bias pot in a Rectifier
Replies: 109
Views: 100739

Re: How to install a bias pot in a Rectifier

Thank's mickey383, I Didn't receive your answer on my e-mail adress. I have to check the forum set up on my profil. My bias circuit are working well, the 2 pots. Yes I want to put 6L6 or EL34 and have bias with easy adjust. This job is for a customers. About the resistors. You are right; omit domest...
by stratele52
Sun Oct 17, 2010 1:53 pm
Forum: Rectifier Series
Topic: How to install a bias pot in a Rectifier
Replies: 109
Views: 100739

Re: How to install a bias pot in a Rectifier

I'm new to this forum and I read the first page of this very interesting post. I'm working now to built a 2 adjustment pots at Triple Rectifier. One for the 6L6 and one for EL34. I did not read other pages, maybe somebody write about that : I noticed on shematic of the Two rectifier, it's write abou...