[Amps] Al-1500 conversion from 8877 to GU-84B

Tue Jul 19 10:25:15 EDT 2005

Tom Adams WB8WJU has done a neat conversion on an AL-1500 where he relaced 
the dud 8877 with a Russian GU-84B.......The price savings by switching to 
the GU-84B tube is about $600.......not bad.
Check it out at.
http://groups.msn.com/tomstubes/al1500conversionfrom8877togu84b.msnw

73
Tom....w4th

Tom's Tubes: Amateur Radio Amp Tubes & Sockets, CTHRD Hand Made CW Keys, 
K4POZ Screwdriver Antennas & G3SEK Triode/Tetrode Boards & Kits. 
http://www.tomstubes.com

----Original Message Follows----
From: amps-request at contesting.com
Reply-To: amps at contesting.com
To: amps at contesting.com
Subject: Amps Digest, Vol 31, Issue 33
Date: Tue, 19 Jul 2005 09:20:45 -0400

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Today's Topics:

1. Re: HF Baluns (R.Measures)
2. Re: HP / Agilent manuals (Kenneth D. Grimm, K4XL)
3. 3CX800A7 (N7KA at comcast.net)
4. Interesting Commercial Marconi BH-30 Linear Amplifier (Colin Gunn)
5. Re: HP / Agilent manuals (David Kirkby)
6. Re: HP / Agilent manuals (David Kirkby)
7. LK500 Amp Problem (Adrian Rees (M1LCR))
8. Re: LK500 Amp Problem (Steve Thompson)
9. Re: LK500 Amp Problem (Will Matney)
10. Re: LK500 Amp Problem (GGLL)
11. Re: LK500 Amp Problem (R.Measures)

----------------------------------------------------------------------

Message: 1
Date: Mon, 18 Jul 2005 09:04:57 -0700
From: R.Measures <r at somis.org>
Subject: Re: [Amps] HF Baluns
To: "Mark Marsden" <mm at plextek.co.uk>
Cc: amps at contesting.com
Message-ID: <a7997a006bc3289acf97b18333922e25 at somis.org>
Content-Type: text/plain; charset=US-ASCII; format=flowed

Mark -- at what power level were the measurements made on the bifilar
balun?

On Jul 18, 2005, at 5:19 AM, Mark Marsden wrote:

>Hi Amp'ers
>
>This weekend I documented some measurements on homebrew bifilar and
>coaxial 4:1 HF baluns. FYI, have a look at
>http://granta.digital-crocus.com/Balun.php3
><http://granta.digital-crocus.com/Balun.php3>
>
>
>73 Mark G4AXX
>
>
>
>
>_______________________________________________
>Amps mailing list
>Amps at contesting.com
>http://lists.contesting.com/mailman/listinfo/amps
>
>

Richard L. Measures, AG6K, 805.386.3734. www.somis.org

------------------------------

Message: 2
Date: Mon, 18 Jul 2005 22:14:07 -0400
From: "Kenneth D. Grimm, K4XL" <kgrimm at adelphia.net>
Subject: Re: [Amps] HP / Agilent manuals
To: amps at contesting.com
Message-ID: <42DC61EF.1000905 at adelphia.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Ian White G/GM3SEK wrote:

>David Kirkby wrote:
>
>
>>>Following the postings some time back about Agilent scanning old HP
>>>manuals to put on their web site, I received an email from Dave
>>>Cunningham at Agilent
>>>
>>>yesterday, in which he sent me an updated list
>>>of what manuals he has which will get scanned and what is still wanted.
>>>
>>>
>>>
>snip
>
>I made some comment to him about not having a list in Excel format, so
>he sent me some pseudo HTML (you can see I don't like Windoze can't
>you?) My browser (Mozilla 1.4 on Sun SPARC) has some problems displaying
>this clearly, but it is readable. I'm suspect those of you using
>Microsoft products will have no problems, although I have not tested it.
>
>
>
>Same problems here - almost unreadable with Firefox, and barely readable
>even with IE6.
>
>
>
>
The file is a Microsoft Excel file despite the suffix. Open it up with
Excel and it displays correctly.
73,

--

Ken K4XL
k4xl at arrl.net

*** BoatAnchor Manual Archive ***
On the web at http://bama.sbc.edu and http://bama.edebris.com
FTP site info: bama.sbc.edu login: anonymous p/w: youremailadr

------------------------------

Message: 3
Date: Tue, 19 Jul 2005 04:58:06 +0000
From: N7KA at comcast.net
Subject: [Amps] 3CX800A7
To: amps at contesting.com
Message-ID:
<071920050458.5987.42DC885E00082E29000017632206424613BEB5C9B2 at comcast.net>

Content-Type: text/plain

Looking for source of good pulls or new tubes. Who has best deal. Need 2 of 
these critters.

73 de Arne N7KA

------------------------------

Message: 4
Date: Mon, 18 Jul 2005 23:40:38 -0700
From: "Colin Gunn" <cngunn at telus.net>
Subject: [Amps] Interesting Commercial Marconi BH-30 Linear Amplifier
To: <amps at contesting.com>
Message-ID: <001d01c58c2c$c6c5f940$02a8a8c0 at toroid>
Content-Type: text/plain; charset="iso-8859-1"

http://www3.telus.net/ve7tnt/

Ve7TNT

------------------------------

Message: 5
Date: Tue, 19 Jul 2005 08:30:13 +0100
From: David Kirkby <david.kirkby at onetel.net>
Subject: Re: [Amps] HP / Agilent manuals
To: "Kenneth D. Grimm, K4XL" <kgrimm at adelphia.net>
Cc: amps at contesting.com
Message-ID: <42DCAC05.9080506 at onetel.net>
Content-Type: text/plain; charset=us-ascii; format=flowed

Kenneth D. Grimm, K4XL wrote:

>>I made some comment to him about not having a list in Excel format, so
>>he sent me some pseudo HTML (you can see I don't like Windoze can't
>>you?) My browser (Mozilla 1.4 on Sun SPARC) has some problems displaying
>>this clearly, but it is readable. I'm suspect those of you using
>>Microsoft products will have no problems, although I have not tested it.
>>
>>
>>
>>Same problems here - almost unreadable with Firefox, and barely readable
>>even with IE6.
>>
>>
>>
>>
>
>The file is a Microsoft Excel file despite the suffix. Open it up with
>Excel and it displays correctly.
>73,

It must be a mixture at least, as the first line of it has start with an
HTML tag - the normal one you would use for any HTML file.

I know when I looked at the file with a text editor, I thought it was
horrible HTML.

--
David Kirkby,
G8WRB

Please check out http://www.g8wrb.org/
of if you live in Essex http://www.southminster-branch-line.org.uk/

------------------------------

Message: 6
Date: Tue, 19 Jul 2005 09:08:57 +0100
From: David Kirkby <david.kirkby at onetel.net>
Subject: Re: [Amps] HP / Agilent manuals
To: Ian White GM3SEK <g3sek at ifwtech.co.uk>
Cc: amps at contesting.com
Message-ID: <42DCB519.9050802 at onetel.net>
Content-Type: text/plain; charset=us-ascii; format=flowed

Ian White G/GM3SEK wrote:
>David Kirkby wrote:
>
>>>Following the postings some time back about Agilent scanning old HP
>>>manuals to put on their web site, I received an email from Dave
>>>Cunningham at Agilent
>
>
>>>yesterday, in which he sent me an updated list
>>>of what manuals he has which will get scanned and what is still wanted.
>>>
>
>
>Des anyone have user and service manuals for the HP8640-A, please?
>
>(Not the B with the digital readout, but the A model with the slide-rule
>scale.)

Sorry,
Ian I can't help you, but ....

I have had an a few ideas recently about test equipment manuals and how
we my get them free.

See

http://www.southminster-branch-line.org.uk/cgi-bin/unstable

(It will at some point go onto a more appropriate web site, but for now
that site is easiest for me, as I personally own and administer the web
server)

Note, at this point in time, pressing the "submit" button will NOT
result in the data being recorded, so don't bother listing your full
name, email, exact details of equipment etc, since it all goes nowhere.

I would however be interested in comments.

Would something like this be useful?

Would any of you be willing to scan part of a manual they own, but not
all of it?

Would you be willing to loan a manual to someone - perhaps with a
deposit? (Someone loaning me the HP 5370B time interval counter allowed
me to produce a manual which I put online, but, which will soon be on
the Agilent site too.)

How could the form at the above URL be improved (I expect there are
spelling/grammatical errors, as it is in an early stage of development,
so don't bother listing them.) Any other questions - any that are not
needed? There will be a free entry text box where you can put additional
information, but that is not there yet.

Please note, I don't wish for this to become a place where commercial
sellers of manuals list what they have, so there will be no questions
about buying/selling manuals.

Ideally the information should be put into a database, but I don't know
much about them, so was thinking of a simple text file which people
could search through with their browser. Perhaps however I will hook it
up to a mysql database - just I have never been interested in databases,
despite their obvious use, and in this case a database would be nice.

Any better way to solve the problem of unobtainable manuals? Agilent
look like they will solve part of it with this effort But I don't think
they are going to do it for every old bit of HP kit.

Note, I whilst I have some tube data sheets at www.g8wrb.org, I have no
intension of storing copies of manuals on a web server - it would take
too much disk space and too much network load. I did it for the 5370B
since I scanned it, but sites like BAMA are willing to host manuals - I
am not. But I don't mind putting something together to help others.

--
David Kirkby,
G8WRB

Please check out http://www.g8wrb.org/
of if you live in Essex http://www.southminster-branch-line.org.uk/

------------------------------

Message: 7
Date: Tue, 19 Jul 2005 09:53:39 +0100
From: "Adrian Rees (M1LCR)" <rees.a at btconnect.com>
Subject: [Amps] LK500 Amp Problem
To: <amps at contesting.com>
Message-ID: <JIELLPOINGFPEDCBDKKJGEELDEAA.rees.a at btconnect.com>
Content-Type: text/plain; charset="us-ascii"

Hi all
We have an LK 500 Amplifier (the pair of 3-500Z's model) that started to
spark and arc quite badly last weekend when we tested it ready for IOTA.

We've had a look at the amp, and it appears that the varnish on the anode
choke has come off, and there are signs of tracking.

Given that it'll need re-winding, what you boys suggest I coat the choke in,
to stop it from unravelling ?

Any other comments ?

Adrian (M1LCR)

------------------------------

Message: 8
Date: Tue, 19 Jul 2005 10:03:47 +0100
From: Steve Thompson <g8gsq at ic24.net>
Subject: Re: [Amps] LK500 Amp Problem
To: amps at contesting.com
Message-ID: <42DCC1F3.9090902 at ic24.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Adrian Rees (M1LCR) wrote:
>Hi all
>We have an LK 500 Amplifier (the pair of 3-500Z's model) that started to
>spark and arc quite badly last weekend when we tested it ready for IOTA.
>
>We've had a look at the amp, and it appears that the varnish on the anode
>choke has come off, and there are signs of tracking.
>
>Given that it'll need re-winding, what you boys suggest I coat the choke 
>in,
>to stop it from unravelling ?
I've never tried it, but how about plumber's PTFE tape? No
worries about losses.

Steve

------------------------------

Message: 9
Date: Tue, 19 Jul 2005 04:13:16 -0500
From: "Will Matney" <craxd at engineer.com>
Subject: Re: [Amps] LK500 Amp Problem
To: amps at contesting.com
Message-ID: <20050719091316.AB3434BEAD at ws1-1.us4.outblaze.com>
Content-Type: text/plain

Adrian,

You want to make sure you hold the magnet wire taught when rewinding it. 
Then the end connections will hold it pretty much in place. Afterwards, get 
a spray can of polyurathane varnish and spray on an even coat. About 2-3 
coats would be good for thickness, just allow it to air dry between coats. 
You dont want anything thicker than this because of heat dissapation. 
Anything that can trap heat into the wire derates its power capability. Make 
sure to use a wire gage to see what size wire the choke was originally wound 
with.

Best,

Will

>
>Hi all
>We have an LK 500 Amplifier (the pair of 3-500Z's model) that started to
>spark and arc quite badly last weekend when we tested it ready for IOTA.
>
>We've had a look at the amp, and it appears that the varnish on the anode
>choke has come off, and there are signs of tracking.
>
>Given that it'll need re-winding, what you boys suggest I coat the choke 
>in,
>to stop it from unravelling ?
>
>Any other comments ?
>
>Adrian (M1LCR)
>
>_______________________________________________
>Amps mailing list
>Amps at contesting.com
>http://lists.contesting.com/mailman/listinfo/amps

--
___________________________________________________________
Sign-up for Ads Free at Mail.com
http://promo.mail.com/adsfreejump.htm

------------------------------

Message: 10
Date: Tue, 19 Jul 2005 10:07:08 -0300
From: GGLL <nagato at arnet.com.ar>
Subject: Re: [Amps] LK500 Amp Problem
To: Amplificadores Lineales <amps at contesting.com>
Message-ID: <42DCFAFC.8010209 at arnet.com.ar>
Content-Type: text/plain; charset=ISO-8859-1

Steve Thompson escribi?:
>Adrian Rees (M1LCR) wrote:
>
>>Hi all
>>We have an LK 500 Amplifier (the pair of 3-500Z's model) that started to
>>spark and arc quite badly last weekend when we tested it ready for IOTA.
>>
>>We've had a look at the amp, and it appears that the varnish on the anode
>>choke has come off, and there are signs of tracking.
>>
>>Given that it'll need re-winding, what you boys suggest I coat the choke 
>>in,
>>to stop it from unravelling ?
>
>I've never tried it, but how about plumber's PTFE tape? No
>worries about losses.
>
>Steve

I've used plumber's PTFE tape to protect the trap coils in my past HQ-1 mini
quad antenna (that for 20,15, 10 and 6), with no apparent loss of 
performance
or de-tuning.
Over it I then sprayed two acrylic spray layers.

Best regards
Guillermo - LU8EYW.

------------------------------

Message: 11
Date: Tue, 19 Jul 2005 06:20:32 -0700
From: R.Measures <r at somis.org>
Subject: Re: [Amps] LK500 Amp Problem
To: "Adrian Rees (M1LCR)" <rees.a at btconnect.com>
Cc: amps at contesting.com
Message-ID: <21b04d29ef5ea19b8613531eea6a1270 at somis.org>
Content-Type: text/plain; charset=US-ASCII; format=flowed

On Jul 19, 2005, at 1:53 AM, Adrian Rees (M1LCR) wrote:

>Hi all
>We have an LK 500 Amplifier (the pair of 3-500Z's model) that started
>to
>spark and arc quite badly last weekend when we tested it ready for
>IOTA.
>
>We've had a look at the amp, and it appears that the varnish on the
>anode
>choke has come off, and there are signs of tracking.
>
>Given that it'll need re-winding, what you boys suggest I coat the
>choke in,
>to stop it from unravelling ?

Hello, Adrian -- I use clear, gloss. polyurethane varnish that I apply
with my finger. A suitable type of Cu wire for HV RFC service is sold
by electric-motor rewinding shops. It is sold by weight. Bring your
own spool. Details on using such is covered in 'Amplifiers', Part 4 on
my Web site.

>
>Any other comments ?

The arcing you describe in the LK-500 amplifier is typically caused by
the combination of the anode's self-resonance c. 100MHz and the 0.3pF
feedback-C in the 3-500Zs. The result is intermittent regeneration c.
100MHz. Since the HF tank is a low-pass configuration, VHF energy can
not pass through, so it runs amuck and arcs the Tune-C and / or the
bandswitch. Decreasing the Q of the VHF suppressors will decrease the
amplification at VHF -- which may stop the oscillation problem. The
tradeoff is an additional power loss of c. 2% at 29MHz.
>
>Adrian (M1LCR)
>
>_______________________________________________
>Amps mailing list
>Amps at contesting.com
>http://lists.contesting.com/mailman/listinfo/amps
>
>

Richard L. Measures, AG6K, 805.386.3734. www.somis.org

------------------------------

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End of Amps Digest, Vol 31, Issue 33
************************************