Vintage Amp Modification

[Raccoon]

Ok, I have to run this by you guys. Maybe one of you has seen something like this before. I recently came across a D & A Raider amp. Since I wasn't familiar with it, I started researching it hoping that to learn more about it. I discovered that this amp was created to be an 11 meter only amp. Despite the fact that the selector switch on the front says 10/15/20 & 40 meters on it . But here's where it gets interesting. The original D & A Raider amps had a small coil inside them, roughly about an inch long. And only one wire coming from the selector switch ... but this one has been modified. The coil inside this one is around 5 or 6 inches long (give or take an inch) , with a wire coming from each section of the selector (10/15/20 & 40) and attached to the coil in the appropriate sections for the matching frequencies on the selector.

So apparently, someone has taken the time to restore this D & A Raider, and also modify it to actually work on the bands that the selector on the front says.

So have any of you ever seen a D & A Raider with a modification like this before ? Because I haven't had any luck trying to find out any information about this on the Internet.

Incidently, before it's commented on. Yes I am licensed to use it on the HF bands. I'm just curious about the modification, it's the only one I've seen like this.

 

[nomadradio]

ever seen a D & A Raider with a modification like this

Nope.

The input circuit is a 10/11 meter-only tuned circuit, so the bandswitch bands would never really work. The Phantom had a switch on the rear panel that would bypass the tuned input, but not the smaller models.

For me, the real hoot is what happens when you try to use it on sideband. The baldy tubes were typically wired for zero bias. The AM carrier would bias the tubes and hold the plate current to a safe level. But with no drive, the baldy tubes would cherry up and fail. If you kept it up the plate choke would be next. If this one was modded to actually work below 27 MHz I'd have to figure it was to use sideband.

Or (gasp), CW?

73

 

[BJ radionut]

I had a D&A Maverick...Found at Hamfest for some ridiculous low price and got it home. The thing must have been a last-ditch effort to pass FCC interference. Band switch 10-40m...Tank Coil was long enough for 40m and tapped to band switch. The kicker was the rear panel had a small 4 position switch hooked to 4 "L networks" ... Worked great on all the bands. The 4 driver tubes were worthless (6jv6's ???) unless you were using a QRP TenTec or Yaesu FT-7 for a rig I used the original config with a Cobra SSB rig converted to 10m from old 73 mag article.
I reworked it to lose the drivers and basically made a DENTRON GLA 1000 that worked 40-10m... worked great.
Later I was going to rework the deck for a GI7B amp "experiment"...Gutted the chassis of most parts. Never removed the old sockets or 3 matched transformers...It's in nice a dry spot in the barn shelves, with other "ampy" parts...Doubt I'll ever find time to mess with it...
New 6m amp and "another" L4B in the "wings"