Tetrode QRO

AB5YG at aol.com AB5YG at aol.com
Sat Apr 6 12:28:42 EST 1996

Garry, NI6T wrote; Building own 4CX1600B amplifier ---

Building your amplifier? Building anything?  Congratulations ---  I fondly
remember those days --
I remember going to "radio row" on Courtland St. in NYC and dragging big
transformers/caps/chokes, Radar Transmitters,  &  whatever else we could
carry back to NJ on the Jersey Central RR. (I liked anything with lots of

My first "big" amp ran a pair of 803's in Class C -- I remember that amp well
-- I developed an everlasting respect for a 2500 volts!!  An old buddy of
mine (K2PBQ now KC4UIJ) stopped by yesterday (Last eyeball QSO was 35 yrs
ago) and we reminnesed about the amplifier we built back in the late 50s that
had thirty 837s in the final. We also discussed the scars still on his hands
from grabbing the smoking cables going from his car battery to the motor
generator set that powered his Harvey Wells Bandmaster, sending CW with car
horns, the car hop and all of that good old stuff ---- Great memories!

Whats all of this have to do with tetrode QRO? - Not much --- I just got
carried away --

Bottom line: I still have my "pride and joy" 2M Amplifier - Just could not
part with it -- I designed and built it back in '67 and have not used it
since 1972!   It uses a pair of RCA 8122s (400W plate dissipation tetrodes)
running in class C. It has RCA air system sockets, strip line input network,
1 1/2" silver plated copper pipe output network, unbelievable shielding and
of course lots of meters.  The amp has a built in Zener Diode string for the
screens and a grid bias supply.  All that is required is a 2500 volt power
supply - HV input to the amp is via a HV BNC connector. I have 2 (never used)
spare 8122s.

I would like to GIVE my amplifier to any ham (that builds stuff) attempting
VHF contesting, 2M long haul, moonbounce, etc., -  that needs a little help.
(pickup from Ocean Springs, Mississippi)

I built the following amps and enjoyed every bit of it ---
6L6s on HF
807s on HF
811s on HF
837s on HF
803s on HF
4-65s on 2M
4x150s on HF
4-400s on HF
4-1000A on 20M
4CX300 on 432      
8122s on 2M 

73 - Bill, AB5YG (ex K2MHJ)

>From Esteban J. Morao" <yv5dta at igc.net  Sat Apr  6 16:43:19 1996
From: Esteban J. Morao" <yv5dta at igc.net (Esteban J. Morao)
Date: Sat, 6 Apr 1996 11:43:19 -0500
Subject: Pavilion Packer Cluster
Message-ID: <01BB23B5.E69381A0 at ftl-fl-1-4.igc.net>

Does Pavilion Packet Cluster has a reflector?

Steve Romagni Morao BSMIS
Systems Analyst 
Allders International
e-mail:yv5dta at igc.net


>From Ward Silver <hwardsil at wolfenet.com>  Sat Apr  6 17:41:23 1996
From: Ward Silver <hwardsil at wolfenet.com> (Ward Silver)
Date: Sat, 6 Apr 1996 09:41:23 -0800 (PST)
Subject: Continental Breakdown Files
Message-ID: <Pine.OSF.3.91.960406093705.25881B-100000 at gonzo.wolfenet.com>

For those that may have missed my earlier message, I'm collecting US/VE
continental breakdown files (.CON from CT and .BRK from TR, ?? from NA)
for an experiment to find out how continental distributions vary across
the NA continent.  I need your breakdown files with your Call and State at
the top.  CT/TR/NA will put your call on there automatically, but please
add your state, as that is how I will break up the data. 

If I get enough data, the resulting graphics and analysis will be 
published in CQ-Contest.  Hopefully, the process will be nearly 
automate-able, so we could get regular feedback on how propagation is 
varying across the continent.

Again, just send me your breakdown files, not the logs, rate, or summaries.

Thanks in advance!

73, Ward N0AX

>From Esteban J. Morao" <yv5dta at igc.net  Sat Apr  6 17:27:02 1996
From: Esteban J. Morao" <yv5dta at igc.net (Esteban J. Morao)
Date: Sat, 6 Apr 1996 12:27:02 -0500
Subject: Power Supplies Sumary
Message-ID: <01BB23B6.0E6A7B20 at ftl-fl-1-4.igc.net>

Well here is the summary I promise abt the power supplies... I think the =
icom ps 30 cough my attention, but i think i will wait to see the one =
that kenwood is promessing at dayton
Steve W4/YV5DTA

Here is the Summary of the message i rx:


You are right!  The power supply is the biggest pain.  Not only for =
it around but airport security.  I have been stopped by confused airport
security while carring it on board in airports in the US and Central
America.  It seems like it never fails.  The TS50 in a suitcase with =
etc. weights less than the power supply.  A friend of mine gave me the
advice to take cables ready for a battery.  Usually you can find a 12 v
battery just about anywhere and a charger that some one can loan you.
Especially if you are in "el campo".   What I have done is to take the
Astron 20a and put a metal handle on one side (the kind that is used in =
equipment) and rubber feet on the other.  It makes it a lot easier to =
around.  I wrap it up in a bag and carry it.  I also carry a screw =
driver in
my bag incase I have to open it.  The funny thing is the guy in aduanas =
Costa Rica knew exactly what it was one time and come to find out he was =
11 meter man.  The TS50, I carry around in an old video camera case and
seems not to cause me as many problems as the power supply.  It is a =
damn if
you do and damn if you dont situation.  I used carry around a TS830 but
thought the TS50 would solve all my problems since it was lighter.... =
The power supply combined makes it all just as heavy.  I guess the =
is I can carry the radio in one hand and the power supply in the other =
so it
does not make it as tiring runing all over the airport.  =20

Anyway, I am looking forward to your discoveries.


Ulis R. Fleming   <>   Radio Amateur: WB3LUI * TI5NW  <>  Shortwave =

Hello Steve,

The power supply in use in my DXpeditions is ICOM IC-35 which=20
supplies 13.8V at 20 Amperes.
It is basically made for use as an internal PS for IC-751A or=20
IC-741 radio, but as it is enclosed in a solid metal case, you can=20
use it as an outboard unit as I do to power my IC-731/735.
It weighs only 1.5 kilos (3 and 1/3 pounds). It is readily obtainable=20
in US at the cost of $240-250 new.
The cable connector is a 6-pin type which just fits ICOM and=20
Kenwood, but you have to replace it with an adequate one for
Yaesu if your radio is FT-840.
Primary voltages 120/240 are interchangeable with a little
73 de  Mine
JA2NQG  AH0F  KC6CW  KC6MS  KC6WW  S21ZZ  V63AN  V63WW =20
VK9LS  VK9NQ  VK9XJ  8Q7CW(92) and others.

Steve, I recommend the Icom PS-35, which is the internal supply for the=20
740/745/751. There is an AC line filter which you'll need to enclose in =
small Bud box, but once you get it together, you have three pieces -- AC =

line cord, filter box, and 8"x8"x2" power supply -- which together weigh =

just a tad over FOUR POUNDS, and will put out 20A no sweat on cw or =
If you use it with a non-Icom rig, you'll need to do a work-around to=20
incorporate an on/off switch, however, as the IC rigs handle that=20
internally to two pins in the Molex connector plug. But, then, you'll=20
need to remove/rewire that Molex connector anyhow to connect to your=20
lesser, substitute transceiver . . . .

73 Gene K7DBV        genewill at ordata.com
Webmaster, QCWA (http://www.efn.org/~qcwa)

Hey guys,

When I used to travel and dx the most common problem I faced was the =
of all the gear that I had to take with me and airline company =
I wonder how the others have solved this problem when travelling alone =
with wife (as I do) and having a HEAVY linear plus 3 el beam and multi =
vertical with you. Once I had to leave about 20 kg overweight to the =
and to collect it after 3 weeks trip. Leaving my stuff to airport would =
costed about 600 USD to me but the guy there was understandable and it
costed only 200 USD!!

Some typical solution that I have used and heard other people use:

1.      Put your heaviest rig in hand luggage (OH2BH suggestion). It =
fine but some airlines are very strict when they see you nearly =
with your 30 kg hand luggage. Normally OK but not in Australia =
Hide your hand luggage when you check in.

2.      For those who can afford it take your whole family and parents =
grannies with you (OH1RY trick). When RY is travelling they are 6 people
together allowing 120 kg luggage or some airlines even 180 kg. That is
enough for a good CQ WW contest trip.

There must be other tricks you have used. I have most often used number =
with pretty good success by having my tranceiver in hand luggage and =
everything low weight and clothing to an absolute minimum. (My wife =
understands that rule).

Airline regulations are very different around the world and different
between companies flying the same route. Some extremes: transatlantic
typically 32 kg or two bags (dimensions set), fareast 20 kg (tourist) 30 =
(business or similar), Pacific between islands various 20, 15 or even 10 =
Some flights even weigh every passenger to calculate fuel amount!!!

Any other comments. If many I can wrap up a summary.

Good dx'g & travel'g    Veke    OH2MCN

There was a summary of PS on the reflector in 1995. the best small
12VDC turned out to be made by Mascot electronics in Norway. It was
also the most expensive.  I guess quality has it-s price.

73  rag oz8ro

Hello Steve,

We usually carry small switching power regulators for our overseas
It is made by a Japanese manufacturer and has a capability of
20A continuous and 25A peak.  AC input can be both 110V and 220V.
It weighs only 870g.
How do you think about it?

E-mail: jh2mra at yk.rim.or.jp

Hello Esteban,

You may like to investigate the Kenwood FP-757HD PSU, it weighs 6.9 =
13.5vDC at 20 amps, for extended periods, like RTTY. Hi.
Can be set for 100/110/117/220/234  50/60 hz, built in audio speaker.

I have carried an Astron 35 to the Carib, no fun, but the FP-757 is a
breeze, even for my 145 lbs body.

GL Eddie, W6/G0AZT (P40RY,ZF1RY,8R1TT etc etc)

Steve, this subject comes up every year here and has been beaten to=20
death--but without a good, clear answer.  I have lots of old messages I=20
could send you but let's see what you get.  Astron is clearly not the=20
answer.  I have both 110v and 220v versions and they are simply too=20
heavy.  Kenwood is said to have something coming out that will be good.
Pls post the responses to your inquiry because this is an important=20
issue.  Thanks and 73, Glenn, W6OTC (mgvinson at crl.com)

Hi Steve,

Icom sells a power supply with the model number PS-30.  It is a switcher =
and therefore much much lighter than your=20
Astron.  Expensive but it does the job.


Hi Steve!

I have a LITTLE Deltron switching power supply:  tiny and light!
About 1/2 the size of a TS-50.  13 VDC @ 21 amps.  Thermal cutout
switch (has never come close!).  Very rugged.  $300+ from Deltron.
 Pricy, but nice!  I've used it on my last 3 DXpeditions.  Voltage
input 70 to ?400 volts.  Very versatile.  MY FAVORITE!!!

I have also an Electroautomotive switching supply.  13.5 VDC @ 22
amps, but it is bigger and heavier than the Deltron.  It is about
the same size as a TS-50 and 2-3 times heavier than the Deltron.
Cost $300 delivered.  I've never felt this supply even get warm
during a contest.

Kenwood is announcing a new switching supply at Dayton.  ?$$$

Good luck!

73, Glenn


Glenn R. Johnson, M.D.        email:      =
grjohnson at vax1.bemidji.msus.edu
Home:  218-243-2611           BBS:        WA0PUJ at K0LAL.#NCMN.MN.USA.NA
FAX:   218-243-2918           Cluster:    WA0PUJ at WA0PUJ (PacketCluster)
Work:  218-759-5000

Steve Romagni Morao BSMIS
Systems Analyst=20
Allders International
e-mail:yv5dta at igc.net


>From Bill Fisher, KM9P" <bill at akorn.net  Fri Apr  5 23:27:24 1996
From: Bill Fisher, KM9P" <bill at akorn.net (Bill Fisher, KM9P)
Date: Fri, 05 Apr 1996 18:27:24 -0500
Subject: See KM9P Station!
Message-ID: <3165AC5C.4605 at akorn.net>

I've scanned a bunch of pictures and put them on the WWW for viewing.  I 
put some comentary in there also while you wait for the pictures to 
download.  The pictures look perfect on a 2MB VGA card.  Not sure how 
good on 1MB VGA cards.  

The XYL (english major) hasn't gone through the editorial yet, so please 
don't bother sending me "hey moron" notes about my spelling or grammar.


Look for Tour KM9P section.

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