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Looking for schematic for Hercules II five transistor mobile amp

X

Xracerx13

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Please anyone.
I am looking for schematic for Hercules II five transistor mobile amp. I can't find any info anywhere. I am going through it and want to check resistor and cap values.

s-l1600.jpgs-l1600 (5).jpgs-l1600 (2).jpg s-l1600 (6).jpg
 

No schematic exists so give up any search. :LOL: Anyway as a follow up to this dead 6 year old post.....and to try and regain some lost history under my forum name due to getting hacked and starting over. If anything its good reading right.
Originally it didn't key up due to a bad keying transistor. Such an easy fix. The preamp transistor also needed replacing. Even though it worked ok, eventually I went through it all and this is what I did....

I replaced all the white square chicklet gum sized caps which were swollen, to dipped 0.1uf(104)1kv's, and added feed back circuits to the 4 pill section, and to the driver section mounted to the cover, which is not shown in the pic.
Beefed up the power coming in through that ground strap with a bunch of solder and by adding a piece of 12g copper wire( i know it looks a mess but it works), and also replaced the frayed red power wire with 14g Teflon wire to power the driver.
The Mylar caps on the input transformers were iffy so I replaced those as well.
Added a 12v light bulb to unkey the TX relay quicker by depleting the stored energy holding the relay closed. Short delay on the panel switch wasn't short enough.
Fresh heatsink compound under each transistor. Added a 120mm fan, doubled up the power wires with dual 10g for + and -, and called it a day.
Its a cool amp, and does about 550-600pep(on a Swan WM3000) and has a SSB bias circuit.

If anyone has the specs for these old TRW PT9849 or PT8854 transistors let me know.

herculesII amp.jpg
 
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Most of the older amps that had TRW transistors used the PT9847 (80 watt 30Mhz) device. The smaller 2 pill boxes used either the stud or flange mount PT9784 (60 or 75 watt 30Mhz depending on the datasheet). The Hercules was the only CB amp I've ever seen that used the robust PT9849 (100 watt 30Mhz).
The driver transistor (PT8854) is actually designed for 2 meters (50 watt 175Mhz) and is similar to a Motorola MRF224. Here they probably used it for the driver on purpose because it would have high gain at 27Mhz and would squeeze every last watt out of the driver stage.
 
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I believe the "12 volt" TRW devices were specified at 13.5V.
Yes, there aren't many TRW datasheets floating around on the net these days. I'm just going by memory as I'm an old fart and dealt with these parts a lot when they were being used. I used to have many of the datasheets back in the late 80's but I left them where I was employed for the next tech when I got a new job. It would be nice if I still had them as you know I would have already scanned them and put them out on the net for everyone's benefit.
Also just for information purposes, not all of the "PT" series devices were made by TRW, some of them were manufactured by Motorola.
 

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