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KB3SBC
02-25-2009, 11:57 PM
I have a TPL commercial rf amplifier and it is factory tuned to 150-160 Mhz. It is capable of 136-174 Mhz and i would like to tune it down to 140-150. does anyone have any expierence with this maybe they can give me some guidance at to where the adjusment is made. It is cost prohibitive to have the factory retune it. Any help is appreciated .

73
walt
KB3SBC

W9GB
02-26-2009, 12:36 AM
Walt -

You did not indicate which TLP VHF amplifier you have.
Here is the Owner's manual for the TPL "Hi-Band" VHF amplifiers.
Instructions for operation and adjustment can be found in these doucments.
http://www.radiowrench.com/sonic/tpl_hi-b.pdf

These products are broadband and designed for Hi-Band VHF service (136-174 MHz).
It should not really require any adjustment for usage in the 2-meter amateur radio band.

... does anyone have any experience with this maybe they can give me some guidance at to where the adjusment is made. It is cost prohibitive to have the factory retune it. Any help is appreciated.
Keep the golden screwdriver in your pocket -- What is on your electronics workbench? Bird Wattmeter? Dummy Load? RF Generator for VHF / Service Monitor?
Why do you think you have an issue??

w9gb

K8JD
02-26-2009, 12:47 AM
MORE POWERRRRR !

WB2WIK
02-26-2009, 03:32 AM
Walt -

You did not indicate which TLP VHF amplifier you have.
Here is the Owner's manual for the TPL "Hi-Band" VHF amplifiers.
Instructions for operation and adjustment can be found in these doucments.
http://www.radiowrench.com/sonic/tpl_hi-b.pdf

These products are broadband and designed for Hi-Band VHF service (136-174 MHz).
It should not really require any adjustment for usage in the 2-meter amateur radio band.

Keep the golden screwdriver in your pocket -- What is on your electronics workbench? Bird Wattmeter? Dummy Load? RF Generator for VHF / Service Monitor?
Why do you think you have an issue??

w9gb

::I agree with GB. TPL is a local company to me and I'm very familiar with their products. The "150-160 MHz" amplifier is mostly just a label. It will work fine on two meters (144-148 MHz) without doing anything to it, at all.

However, some TPL amps are Class C only (FM) and will absolutely not work other modes other than FM (no SSB, no AM, etc). If you're working only FM, the amp exactly as it is should work fine on two meters.

WB2WIK/6

K7MH
02-26-2009, 03:47 AM
There must be a million of those TPL amplifiers out there!!

W9GB
02-26-2009, 02:25 PM
I have the PA3-1FE it has sticker on the side of it factory adjusted for 150-160 mhz the spec panel on the other side indicated it can be used for 136-174 mhz.
When I tried to transmit out of the 150-160 mhz range the relays click and no RF comes out. Transmit in the range it works flawless.
I called the company they advised it can be adjusted at a cost of $95.00 its just not worth it, I have limited gear for testing just the basic meters and dummy loads.
thanks,
walt
When I provide manual Internet links, I really expect for people to take the time and examine or read them.
Your specific answer for this model PA3-1FE (1202C) is there in the manual!

How to Adjust, Re-tune these amplifiers is spelled out in the manual. List of test equipment needed; step-by-step instructions and diagrams for connections.
Owner's manual for the TPL "Hi-Band" VHF amplifiers.
http://www.radiowrench.com/sonic/tpl_hi-b.pdf

IF this is beyond you, perhaps a local Elmer or Technical group from a local club can assist you.

w9gb

KB3SBC
02-27-2009, 02:13 AM
Yeap its there in the manual. I appriciate the manual and I should be able to get the adjustment so that the relays click in and stay in instead of the machine gun noise. Thanks to all for your help and kind advice.

73
Walt
KB3SBC

K7FE
02-27-2009, 06:15 AM
Trivia about TPL. The company name TPL was taken from it's founder, Thomas Paul Litty, K6RAD - SK.

Tom and I started a company in 1966 called TNT, (Tom and Terry) building guitar amplifiers, a speech compressor and a "Fuzz" box for guitars. (Tom was a guitarist in a band that played at local LA clubs when he was a teenager.) We continued to be close socially and "double dated." We made a little money on our side business while I was at TRW Semiconductors and He was at Teledyne. I told Tom of an applications engineer position at TRW Semiconductors around 1967 (or 68) which he applied for and was hired.

Tom married Diane and we celebrated with them at their wedding. At TRW, we were both involved with early bipolar RF power transistor development. A few years later discussions led to starting an electronics company again. The new company was to be Tom, another Tom, Carl and I. Tom Litty and I would develop products, Tom Bidar would run manufacturing and Carl Colabella was marketing/sales.

I had recently founded ADAR, which had just received a Navy contract, so I decided to stay with it and not join Tom and the others in what became TPL. That was around 1971. One of their first contracts was building Solid state VHF, class C amplifiers for Henry Radio. They were shipped with the Henry label on them. I believe that Standard Radio's VHF marine amplifiers were built by Tom also. Later Tom became quite successful marketing his own brand of amplifiers, TPL.

Tom died far too young.

73,
Terry, K7FE

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