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PALOMAR TX 100

Thanks for all of the info and history about the Palomar name and Messenger amps. If it is a Messenger (and the internals do appear to match) I can only find models above 100w.

357, What "model" or how many watts is the amp in the picture?
 
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Got a reply from Palomar:

"Ron
Thanks for the email. That unit does not look familiar. I don't think this was made by us. Sorry.
Eric"

I guess I can test it to see if it works but would like someone to put in on the bench and find out what is up.

Here is the vertical board towards the back. Receive preamp maybe?
View attachment 25391
View attachment 25390

Yes, one side is the keying circuit, the other is the receive pre-amp circuit .....
 
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Biased AB for SSB? I'd say close to 250W - but that is what it's label would say...

IF you get that, for SSB modes - on carrier like AM or running FM you'd be lucky to have 100 - 125 W or so on the carrier side....

The Ferrite design alone is for 200+ watts. They are also Morotola "Blue Dot" - a match set scheme but still references to "red - dot" matching. Quality issue - don't let it go to your head and don't blow it...

More than likely these are MRF454 - so you'd see 80W max out of them...good find though - these babys can handle Swing - because they are made for SSB modes (note simple 4001 style diode in 1st pic on power bias rail on the top of the photo simple AB bias) can handle the input dynamics (impedance range to power level input swing) a little better than a 60W 455...so they don't have as "narrow" of a window before your "pinch up".

Note the winds - 3 to 3 - so the amp may fight you a little as far as SWR is concerned not a biggie. But, as othrs are telling you, again keep the power level low - you should be ok. But, run a Limiter (keep it in place) though - that is a low-level drive amp. To run an amp like this for say a PC-122 or SSB ducky - you'd set an SSB radios ALC to about 8~10 watts to keep it from cooking burgers on the grill...(tarnish)

it does have a delay so you may need to look it over and see if remote key is a better option...More than likely the switches focused on RX and SSB delay as well as TX power.
 

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Internally and externally this amp does appear to actually be a Messenger M250 as indicated by 357 above.

Screen Shot 2018-09-28 at 6.39.18 AM.png

Easy enough to find the specs and schematic for M250, but nowhere can I find the stated power output for Low, Medium and High. Assuming under optimal conditions that High is 250w, what would the estimated output be on Medium and Low setting?

I still haven't fired the amp up yet and might run it solo for a while to enjoy SSB. Just wondering if I do eventually use it to push a Fatboy straight 6 for AM only, should I run on Low, Medium or High to get the most out of the Fatboy without overpowering it?
 
nowhere can I find the stated power output for Low, Medium and High.

5 X 5,
I wouldn't be too concerned about the stated output of the "Low, Medium and High" power settings as the "Advertised" output of these devices (as well as "Model Names" i.e. "Tornado 500, Hooker 250 or Volcano 10K) were very optimistic and quite the "Sales Gimmick". If the manufacturer calls it a 750, it must be capable of 750w output.

Your own real world testing would be the best to go by. Operating the amp into a dummy load at each power level will tell you much more than a crumpled sales flyer that is 40 years old. As others have posted here, and in other threads, the transistors are only capable of so much output-under ideal conditions. Doing your best to create those ideal conditions (i.e. proper match to your transmitter, proper termination, at or less than maximum drive power per device, correct voltage for the device and enough current available at the correct voltage for the device, adequate cooling available to the device) will give you much more information than the "Overly Optimistic Sales Pitch".

Just wondering if I do eventually use it to push a Fatboy straight 6 for AM only, should I run on Low, Medium or High to get the most out of the Fatboy without overpowering it?

I don't know anything about a Fatboy Straight 6 (except when I look in the mirror!:ROFLMAO:) but assuming that your "Palomar" will output 250pep at it's maximum setting, will the Fatboy take that much drive? I would start at the lowest setting on the "Palomar" and work from there. The same rules for maximum output apply to the Fatboy "the transistors are only capable of so much output-under ideal conditions.

In my feeble mind, input drive power used should be limited to the maximum tolerated by the next "stage". Example-No more out of the "Palomar" than the "Fatboy" can take.

Good luck. Please post your results.

73's
David
 
Ray used to put his initials on the board when he built them.
5x5
My bet is that the transistors in you amp are MRF 455 transistors under that strap.
Nomad and exit 13 are correct, this looks just like the boards that were being used by Messenger back then.
The color and strip line design are the same.
As Nomad said there were dozens of clones.
They did it to everyone , called them what ever they liked boomer, gray, grey, palamor, palamar, green lizard, red devil, commander, shooting star, palamor elite, some just had a black face with a number on them like 250, 400, 900.
The later ones had vertically mounted input/output transformers.
Almost all said AB1 regardless it they were or not.
The number on the front of the amp is often wishful thinking.
On the original Palamor , some were just model numbers like the 5300 multi band amp and the TX line like the 5500.
Very similar was the Magnum line, I had a Magnum 6000 that had 4x2879's with regulated bias and thermal tracking.
The tx 75 and 100 were close.

Others like TNT ( not x force tnt but the company TNT from back in the 80's) had model numbers that were not to far off what the amp would do.

They built a 200+ that had 4 Motorola 454 transistors in it and if I remember correct the TNT12 pack had MRF 492 transistors.
Pride also had models that approximated the output.

The MRF line of RF transistors have not been made for a long time.
The SRF transistors were matched Motorola transistors with RF Parts house numbers on them
Beta matching was also done in matched pairs, matched quads etc.
Red dot, blue dot, black dot.
Baby that amp, it is a historic item lol.
I have seen them with blue, white, black and gold faces.
Seen them with Motorola MRF 455, 454, SRF 3749, SC1446 and others.
Just treat it as a 100 watt amp.
Nice find.

73
Jeff
 
Ray used to put his initials on the board when he built them.
My bet is that they are MRF 455 transistors under that strap.
Nomad and exit 13 are correct, this looks just like the boards that were being used by Messenger back then.
The color and strip line design are the same.
As Nomad said there were dozens of clones.
They did it to everyone , called them what ever they liked boomer, gray, grey, palamor, palamar, green lizard, red devil, commander, shooting star, palamor elite, some just had a black face with a number on them like 250, 400, 900 and on and on.
Almost all said AB1 regardless it they were or not.
The number on the front of the amp is often wishful thinking.
On the original Palamor , some were just model numbers like the 5300 multi band amp and the TX line like the 5500.
The tx 75 and 100 were close.
Others like TNT ( not x force tnt but the company TNT from back in the 80's) had model numbers that were not to far off what the amp would do.

They built a 200+ that had 4 Motorola 454 transistors in it and if I remember correct the TNT12 pack had MRF 492 transistors.
Pride also had models that approximated the output.

The MRF line of RF transistors have not been made for a long time.
Baby that amp, it is a historic item lol.
I have seen them with blue, white, black and gold faces.
Seen them with Motorola MRF 455, 454, SRF 3749, SC1446 and others.
Just treat it as a 100 watt amp.
Nice find.

73
Jeff
Thanks for the info. Looks like a pair sd1446 under the straps
 
I just recently purchased a Palomar tx-100 and 4 other old 23 channels for $25 that i thought would not work by the looks of everything i figured they had sit in somebodys barn for 30 years from the dirt but not rusty at all.
The inside of the amp was suprisengly clean so i cleaned a little bit of dust out of it with a new paint brush then hooked it up and been talkibf on it non stop for a week now driving it with a little uniden pro 505 and a 30 amp power supply.
It does a little over 100 watts doesnt seen to reflect any waattage back to the radio with good clean audio all the way.
Utterlly shocked to see a barn find turn out so good.
 

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