LAFAYETTE HA-250 LINEAR TUBE MOBILE (HELP???)

[DOC PEPPER]

Got this cute little 2 tube amplifier off eBay and when it got home, there;s no power cord.. just a tube like HEX male plug in the back ??? How do I get a plug or just find out which (pins) on this monster can I power it up with either 120vac or 12vdc .. I've downloaded the manual, but the schematic shows only a 12 volt in the bottom, IT DOES NOT SHOW WHICH PINS ARE WHAT?

 

[nomadradio]

The only schemo I have just shows a hot and ground power input. No 8-pin plug at all.

Don't quite see how the tiny pins on that plug would carry the current required for a power hog like this box.

Haven't looked elsewhere yet.

73

 

[nomadradio]

Google turns up a handful of sites with the exact, same manual and diagram.

Drat!

73

 

[DOC PEPPER]

Seems that this Lafayette Linear amplifier is a MYSTERY out there - NO ONE has that 8 pin diagram ?? All I want to do is either by-pass this mystery with 2 wires ( 12VDC) that's all , and don't what to destroy anything , so if anyone's up to the challenge .. good luck I owe ya a cold one!!
Doc

 

[unit_399]

DOC -
Your amp is vintage 1966, and operates on either AC or DC. Several Lafayette base radios of that time would operate on AC or DC too, and used the same 8-pin power plug as on your amp. It seems logical to me that Lafayette would use the same power plug pinout throughout their line. So I dug into my old SAMs and found a Lafayette base (circa 1965) that had the 8-pin plug. The photo below shows the pinout for both AC and DC inputs. I can't guarantee that this is the same pinout as on your kicker, but maybe worth a try.

Good luck and 73s.

- 399

 

[2RT307]

Reminds me of the AC/DC power plug on my Robyn T-240D.

73,
Brett

 

[unit_399]

Reminds me of the AC/DC power plug on my Robyn T-240D.
73,
Brett

Yupp ... same plug but different pinout.

- 399

 

[nomadradio]

Um, I wouldn't try 120 Volts AC on that one. It has a ferrite-core transformer, pretty sure. Not meant for 60 Hz.

The base-station power socket might or might not match this radio. If memory serves, Lafayette didn't use the exact same power-socket hookup for every base/mobile radio they sold. Just a vague recollection. Could be wrong about that.

The reason for all those pins was to use jumper wires across them to re-wire the radio's power switch, along with feeding power to one set of pins for AC and one set for DC. Using jumper wires inside that plug saved them the cost of a "AC-DC" switch mechanism.

Finding out where each wire goes on that 8-pin socket is the starting point, I think.

ERRRR. Just noticed a slide switch on the rear panel. What is this switch marked?

73

 

[Jay Mojave]

Hello All: Yeah great info here in this thread. Yeah what does the slide switch do or how is it identified?

Had a local with a HA-250 amp, a stock radio, and a M-125 antenna, and it worked great could hear him all over the place, even shoot skip with it. Boy does that bring back great memories.....

Jay in the Great Mojave Desert

 

[DOC PEPPER]

Um, I wouldn't try 120 Volts AC on that one. It has a ferrite-core transformer, pretty sure. Not meant for 60 Hz.

The base-station power socket might or might not match this radio. If memory serves, Lafayette didn't use the exact same power-socket hookup for every base/mobile radio they sold. Just a vague recollection. Could be wrong about that.

The reason for all those pins was to use jumper wires across them to re-wire the radio's power switch, along with feeding power to one set of pins for AC and one set for DC. Using jumper wires inside that plug saved them the cost of a "AC-DC" switch mechanism.

Finding out where each wire goes on that 8-pin socket is the starting point, I think.

ERRRR. Just noticed a slide switch on the rear panel. What is this switch marked?

73

Hi this is DOC ,
I want to thank you guys for the great detective work.. Here's a pic of the switch in the back ( say AM - SSB) on it..

DOC -
Your amp is vintage 1966, and operates on either AC or DC. Several Lafayette base radios of that time would operate on AC or DC too, and used the same 8-pin power plug as on your amp. It seems logical to me that Lafayette would use the same power plug pinout throughout their line. So I dug into my old SAMs and found a Lafayette base (circa 1965) that had the 8-pin plug. The photo below shows the pinout for both AC and DC inputs. I can't guarantee that this is the same pinout as on your kicker, but maybe worth a try.

Good luck and 73s.

- 399

View attachment 21266

GREAT DEYECTIVE WORK - THANKS SOOOOOOOOO MUCH!!
I am greatefull that we still excellent data out there.. much appreciated - I'll give it a try at least with the 12V only to see what goes. DOC!!

 

[nomadradio]

The "AM-SSB" marking pretty well explains what it's for. Puts a capacitor into the keying circuit that holds the relay closed for a half-second or more. The keying circuit normally depends on a steady AM carrier to keep it keyed. No carrier on sideband, so this delay serves to prevent the relay from chattering in time with your SSB modulation.

Still haven't uncovered any reference to this model with that socket on it.

73

 

[DOC PEPPER]

Well folks, my Lafayette powered up today, tested fine , BUT , I had to recheck the wiring. Unfortunately, this baby wasn't wired like the rest and I finally got it going. For information's sake, I drew a hand scematic of my wiring it to a DC 12 Volt power supply and it works good. Feel free to comment.. Now if it will work with AC power, that's another story, but I'm happy as it is now. DOC PEPPER

 

[Jay Mojave]

Hello DP: Ok good deal glad to hear ya got it humin and buzzin. How much power do you get out of it?

These little low power amps were a big deal in the day, late 60's early 70's. They were a blast of interest to the massive CB'ers to get out better. Along with better antennas and such.

Jay in the Great Mojave Desert

 

[DOC PEPPER]

Yep , got from 40W peeking 55W max ..nice vintage oldie..
I'm amazed that there wasn't much data out there on there, accept of course SAM books references.. Anyways, I re-wrote the schematic somewhere before this reply , and was able to power it up. Tested both tube and they are fine also.
DOC PEPPER

 

[unit_399]

DOC -

Glad that you were able to get it working. Enjoy and 73s.

- 399