Hooker 100 ?

[Cabover Bob]

Spent $20 on this, did I do any good ? Can't find info on here........

 

[Big Kahuna]

$20 for a Hooker? I'd say you did well but it really depends on the condition of the Hooker and how well it puts out.

Sorry, couldn't help myself.

 

[Cabover Bob]

Well it was a North Bay find, not West Oakland.......or Wilson Way....

New to the hobby, wasn't aware that there were TRW transistors out there....

 

[Dmans]

did I do any good

Yes

73
David

 

[Slowmover]

$20 for a Hooker? I'd say you did well but it really depends on the condition of the Hooker and how well it puts out.

Sorry, couldn't help myself.

Beat me to it. And did a much better job. I see you’ve been reading in The Epistle of St Homer to have fit words so well to radio conundrums. (Let’s flip the red herring out of the barrel by having “answered”, and place foot firmly on the literal, henceforth).

.

 

[nomadradio]

wasn't aware that there were TRW transistors out there....

TRW made RF power transistors when they were new and high-tech. And Monsanto made LEDs and LED display digits. So did Texas Instruments and Hewlett-Packard. But that was over 40 years ago.

When those products stopped being new, the designs were sold to "generic" producers, not unlike the way medications have a name brand when they're new, and not so much when they go generic.

High-tech companies are always on the prowl for what's new, what's next. And continually tossing overboard what came before.

73

 

[Cabover Bob]

In the case that these TRW PT9839 transistors are dead, is there a suitable stud mount replacement ? I know zero about this stuff, other than I cannot find a single bit of information online specific to this part number.

RF Parts has some options as well as an ebay seller in Greece.

https://www.rfparts.com/rftransistors/transistor-mrfsrfm/rftransistors-mrf-400/mrf450a.html

 

[nomadradio]

I would have suggested the MRF455A. The "A" letter suffix seen on a Motorola MRF part number tends to indicate the stud-mount version of a transistor. Same number lacking the "A" is usually flange mount style.

The MRF450A is rated at 50 Watts each. Better than nothing. Stud-mount types get more scarce every year. The ones that were most popular disappeared first. Makes me think that a part rated at only 50 Watts didn't get a lot of attention.

Gouging out the hole in the circuit board to accept the flange-type transistor is a task I never volunteer to try. Never mind tapping 4-40 threads into the heat sink.

73

 

[Cabover Bob]

I was actually looking for 455A but couldn't seem to find any. Not even sure what condition these 9839's are in until I have it looked at. The 450A was just the most economical, I have absolutely no idea what the best option would be performance wise. There is an ebay seller that has a lot of xxxA transistors in Greece.

Thanks for your response Nomad

 

[Cabover Bob]

I would have suggested the MRF455A. The "A" letter suffix seen on a Motorola MRF part number tends to indicate the stud-mount version of a transistor. Same number lacking the "A" is usually flange mount style.

The MRF450A is rated at 50 Watts each. Better than nothing. Stud-mount types get more scarce every year. The ones that were most popular disappeared first. Makes me think that a part rated at only 50 Watts didn't get a lot of attention.

Gouging out the hole in the circuit board to accept the flange-type transistor is a task I never volunteer to try. Never mind tapping 4-40 threads into the heat sink.

73

Still cannot find any info on these PT9839 transistors, got my hopes up for a moment, but K7FE went to a better place in 2017.

TRW Transistor catalog (Phillips ownership)
http://f6csx.free.fr/DOC/VRAC/Transistors TRW.pdf

Terry, K7FE is an excellent resource on TRW RF transistors.
He worked in Research and Development at TRW Semiconductors in the mid 1960's to early 1970's.
He did write some data sheets and application notes. He may be able to suggest a replacement,
if you provide more information.

TRW Markings - Decoding (example: PT9805 7602)

1. The PT stands for TRW Power Transistor
2. 9805 is the TRW Part Number (98xx series appears to be the group for 28mhz)
3. 7602 is the Date Code. (Device built in the second week of 1976.)
===
What happen to TRW Semiconductor and PT series of RF transistors?

Raytheon (Lexington, MA) acquired the TRW Semiconductor business on September 25, 1992.
https://en.wikipedia.org/wiki/TRW_Inc.#Semiconductors_and_computers

In November 27, 1997 Fairchild Semiconductor acquired Raytheon Semiconductor.
Fairchild had plant operations in the Philippines.

It is difficult to find TRW "PT" data sheets for the 1954-1992 production period of
Pacific Semiconductors-->TRW Semiconductors.
SOME PT numbers were OEM licensed from Motorola designs

From this I determined that mine were made mid '76 and that any data sheet would be difficult to obtain.

Hoping to have it checked soon and prepared to get 450A or 455A replaceds. Will the architecture (?) in this cheesy Hooker box support either or both of these options ?

73

 

[Cabover Bob]

Well I found the Hookers sister........
I also found in a different thread some pics of a Hooker 100 with 455A pills, but the 453A has a slightly higher rating (and cost), any reason why they would not work ?