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Varmint Linear Base Amplifier XL-600, tubes + schematic diagram

Jun 12, 2011
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Hello all;
Let me start with an introduction as I feel I have finally found home here at WorldwideDX.

My name is August Cassiato Jr. My handle is Astro, call sign KYY1525 based in Gainesville Florida, U.S.A.

My father's was a Signal Corps. 2nd Lieutenant enlisted in the early 40's and was so efficient working with any electronics & with fixing equipment that he didn't even think about it he just looked at something and said there it is and fixed. His call sigh was WA4TSV. I hope some may recall him although; he went to be with our Lord in 1983.

I tell you truly, his shoes where too big for me to fit into.

After a brief stint in the U.S. Army 101st AB, 4th Battalion, Battery E, Fort Sill OK; I came back home to Gainesville with a back injury.

Father was very mad and called a lot of people that eventually lead to my case for a claim of partial disability was denied, shut, and locked.

A few weeks ago a friend knowing the love I have for HF radio electronics & for repairing things (as best I can) gifted me with a Varmint Linear Base Amplifier XL-600.

Its tubes & skit missing (of course, & main point of this thread) I have no idea which tubes it takes but I suspect that two are driver & four are finals since there are six sockets. Two are 9 pin & the other four are 12 pin (even forgot the names of the sockets and tubes tetrode is all that keeps coming to mind and I KNOW that is a four pin tube / socket.)

As I am sure, it is apparent at this point I am lost without a skit or father.

So bad knee & back problems or not I went fishing in a 10 X 30 warehouse for the old test equipment.

Praying the whole time, I dug out the Hitchcock tube tester, tubes, meters.

No sign of the old O scope and signal generator but there as old as this Varmint (the old Techtronic’s scope is still missing. I only have one slide out case that has one input and there where others but I think father gave them away.

I would like to find some used equipment to buy after I fix this so let me know of anything people may not want anymore, I can cover shipping.)

So were to turn and do next is the problem dead ends.

As hard as it is to climb (I be having a TKA of my right knee in 10 weeks so this is more then busy work, (Lord Jesus please be with me.))

I got the tube tester out and have been digging for my tube stash, which I thought I had a bunch of the old TV H.V. fly-back, & sweep tubes but only found signal and small amp tubes.

I am not sure but as they astronomically expensive, I will never get this thing to work short of a miracle although I can dream.

I'm flat lost and not too proud to say it.

I believe that 8950's or 6LQ6's are suspect.

What I am sure of is there are two different kinds of tubes required for the Varmint to breathe again!

When I looked up the tubes I thought they were, I had sticker shock!

These are way out of my price range as I am sure everybody not just the disabled people struggle as it is.

Well, they are missing as is the base plate (where I suspect the skit was is at large) it also has two components half way connected. See link to photos at the bottom of this page.

I can clearly see where there are three Electrolytic caps are with one connection broken and a regular cap with one connection in place. Where the other goes is?

Does anybody known where I can find its schematic and what tubes the Varmint Linear Base Amplifier XL-600 can be found or obtained?

PLEASE HELP.

Thank you kindly for reading my life's story. LOL

Astro (KYY1525)

Please see photos at:

Welcome to Windows Live

Thanks to everyone & 73's :headbang
 

Welcome to the Forum!
One of the members here had a XL 600, user name is 555
Not sure if he still has it.
Also there are a few here that play with some sweep tube amps.
Also, I will move this thread over to the Amplifiers Section and we can see if someone can lend ya a hand.
2 driving 4 sounds right, I will take a shot here and say 2 6kv6A`s driving 4 6LF6`s
There are subs for the 6lf6`s, you can use 6JS6C`s or 6LB6 tubes.
I can not see the pictures, as i do not have an account with windows live, but you can post them here as an attachment, that might help sort out what has been unhooked.....lets see if some of the guys can jump in here with some more info.

73
Jeff
 
URGENT! Varmint XL-600 NEEDS CPR! HELP, see photos.

Thanks a lot. I'm REALLY new at this.

Since I can't do much until they cut out my knee & stick in a new one, all I can is sit here. I got to do something or I would loose it.
:bdh:

Thank you for taking the time to help.

It was suggested that Mr. 555 might have a skit or info on this darn Varmint (pun intended).

Also I was told the Varmint XL-600, 2 driver & 4 finals might be say 2 6kv6A`s driving 4 6LF6`s
There are subs for the 6lf6`s, you can use 6JS6C`s or 6LB6 tubes.

Okay, I copied & pasted the tube stuff here.

I don't know where or if I should be concerned, where NOT to buy tubes from?

Should I buy new or used?

Does anybody know of a set of these six or more are for sale reasonably cheap (that work at at least 75% power?)

I would love to see this Varmint glow again!

Photos attached. if you need a different view, just let me know.

I get them to you all.

73's
:headbang

Astro
 
Might as well change out the electrolytic caps in it. Sure would help your chances of making it run/sound right. Finding electrolytic caps for high voltage applications is as easy as looking them up online. Little buggers are expensive - though! Same for the resistors.

Got pictures?
 
Yes sir but I can't figure out why they won't upload I did it twice hit the browse selected three then told it upload and it just sat there then timed out. After two times of that I thought I would ask someone how to and what format the digi cam is another new one on me. Boy am I getting old!
Varmint%20Linear%20Base%20Amplifier%20XL-600
 
Hi,

You're missing a lot more than tubes. Someone really did a number on the pi-network... looks like you are missing both the tune and load caps. The tank coil & B+ blocking caps are still there.(good) I've owned several of the Brewer Labs amps over the years and never found an schematic. You can try "cbtricks" but everything there is for the last line of amps they built.

FYI the plate on the chassis beside the transformer is for a second transformer. the 750 & 1000 ran two of them. Same chassis used for years.

Match Stick
 
varmint xl 600

I have a varmint xl 600 right here and let me tell ya it does the job well you can get tubes on Ebay here Palomar Skipper 300 Amp Tube Set 8950 to 6LB6 6KD6 6LF6 6LR6 Conversion Kit | eBay the 6lf6 $110.00 for a set of 4 my varmint works good but the other day the pre amp went out on it but other then that its a talker let me know if you need some pictures of the in side of it I can send you some
 
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that thing is a collection of parts better used to make a decent amp with.
i have a xl250 here that is more complete but have no desire to repair.
if you do fix it up i would change over to el509/519 tubes.
but its likely a waste of time and money.sweep tube amps were tolerated back in the day because the tubes were cheap and plentiful.
no more.
 
that thing is a collection of parts better used to make a decent amp with.
i have a xl250 here that is more complete but have no desire to repair.
if you do fix it up i would change over to el509/519 tubes.
but its likely a waste of time and money.sweep tube amps were tolerated back in the day because the tubes were cheap and plentiful.
no more.

Unfortunately the EL509 tube was also discontinued about 7 years ago and now costs as much as a 6LF6 or 6LQ6. The last production runs that are available today as NOS were also complete junk in comparison to earlier runs. The oxide coating on the cathodes are paper thin and only produce full emissions for about 20% of the normal life span.

To confuse matters even more the Russian factory reused the same EL509 number on a new audio tube. I can't explain what a stupid idea this was to do since many people have now ordered the wrong tube only to find out the socket is different and it has no anode cap on top. It may say EL509 but it's obviously not.
 

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