Sidebar Sidebar
  • You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
  • Click here to find out how to win free radios from Retevis!

12TUBE D&A PHANTOM 500 SCHEMATICS


Hey NOMAD,
A few guys is telling me my Browning mark III sounds like it’s on side band on channel 20.
It's only on channel 20 I swapped the channel 20 Crystal with one from another browning that has keying issues.
But I don't know if it was a good crystal they both have the original crystals.
 
Crystals drift with age. Using a tiny perhaps 1- 5 Pf trimmer. A frequency counter. The crystal could be pulled to oscillate at the right frequency. Custom crystals are expensive. If not mistaken. Only a European company will make them.

My Glen VFO still works. But I am using it on another crystal vintage CB.

Though I have not tried it. This fleecBay VFO looks quite promising. Cheaper than Crystals. Of course. A few other items would have to be purchased. EG connectors.

https://www.ebay.com/itm/Digital-0-...962793?hash=item2618ed4f69:g:IR4AAOSwXdlcoYnU
 
  • Like
Reactions: Shadetree Mechanic
How much for two 7.8 MHZ crystals with a passband of 3 at the center matched?

Will use it as an IF filter.

My 40 ear old digi scan works fine. A bit off. But an $8.00 shipped frequency counter
that I attached. Keeps it dead on !.

I buy a lot of Sweeps on Fleec Bay. I have to hit the RETURN button at least 30% of the time !
It is listed as USED the Glen. No work. Hit the return. Its a Crap Shoot ! Shoosh I might bid on it. Nah have three. All work. Might FleecBay them after re-cap and tune !
 
This is the solution we offer to expand the coverage of a Mark 3 SSB transmitter:

lH8mag.jpg


When we get a batch of a half-dozen or more ready to sell they go onto Ebay.

Direct price is 200 bucks plus shipping.

Fair warning, not always in stock.

73
 
  • Like
Reactions: Shadetree Mechanic and BJ radionut
While we are on the D&A subject, who did Ed have make his re-branded D&A tubes? Was there anything ruggedized or special about them?

Also, would anyone have a schematic for the Warrior? I have the older one with the grey cases and the 4x4x8 with keying tube. There is a variable on the front that needs some work and I need to re-cap it.

Thanks,
Dr_DX
 
I don't remember who made the "D50" rebranded tubes that had the name "D&A" printed on them.

I do know that you could get any name you want printed on tubes if you bought enough of them. The factory shipped them with only the type number, in bulk trays of 144.

The name got printed on them by the wholesale distributor, who also put them into individual retail-sale cartons.

I had a tech here who started to trace down and draw up a schematic for the Warrior. Just one problem. Someone had already scrambled wires in it. Kinda slowed him down. The tech in question went out west for a camping trip before finishing that project and disappeared.

Literally.

Got reported missing in the Gifford Pinchot National Forest in Washington state. Found his car and campsite. Search parties came back empty-handed.

Still missing almost four years later.

No way I'll undertake that project for free. Not much chance anyone would pay for the labor it will take.

Best of luck and 73
 
Dr_DX said:
While we are on the D&A subject, who did Ed have make his re-branded D&A tubes? Was there anything ruggedized or special about them?

Also, would anyone have a schematic for the Warrior? I have the older one with the grey cases and the 4x4x8 with keying tube. There is a variable on the front that needs some work and I need to re-cap it.

Thanks,
Dr_DX
Click to expand...
The double strapped plated 6LQ6 with the black cap is more rugged than the standard version with a silver cap and single plate wire. Because of this they were very popular in high end class A tube audio amps like Macintosh. I'm only aware of two US manufacturers that made this tube. RCA made many but GE's plant in Owensboro KY made some too. RCA did not have an interest is selling their receiving tube line for transmitting applications and resisted such requests. GE on the other hand would do almost anything if the customer paid for enough tubes at once. Everyone from Tram to Maco used GE tubes in CB land. Maco even convinced GE to drop the guts of an 8908 into a 12 pin compactron envelope rather than the octal base to form the M-2057.
 
  • Like
Reactions: Dr_DX
The original 6JE6 tube was used in RCA's large-screen (21-inch and 23-inch) color TV models of the 60s. These sets had a failure problem in the field. If the drive signal to the tube failed, it would immediately overheat. The bias voltage that controlled the tube's current was derived entirely from the drive pulse feeding into it.

The result was that if the tiny 6GH8 tube driving it were to shut down for any reason, the tube would cherry, melt the glass and blow out the expensive horizontal-output (flyback) transformer as well.

Bad news was that this kept occurring to sets under warranty. There were some house fires that got news coverage at the time.

RCA came up with a couple of fixes for this. First was to design a special circuit breaker with two inputs. The normal side was in line with the AC line cord. A second element went from the cathode of the horizontal-output tube to ground. If that tube lost its drive, it was supposed to draw enough cathode current to safely trip the breaker.

Safely, maybe. But not for the tube. The new breaker would protect the TV owner's house but not the horizontal-output tube.

Around 1968 or so RCA redesigned the 6JE6 with thicker high-temperature glass that wouldn't soften as easily, a heavier anode, and a "hard-seal" plate cap that had a black coating. Pretty sure the coating was to make it bond to the glass. The previous tube had only a thin wire from the anode, through the glass and soldered to a hollow brass plate cap glued to the envelope. This "black" plate cap was bonded to the harder glass around its entire 3/8-inch outside diameter.

I'm still looking for a copy of the advertisement I saw in Popular Electronics when the new, beefier "6LQ6" tube was introduced. The claim was that the anode would dissipate 200 Watts for 30 seconds without damage. Now RCA had a tube that would pop that dual circuit breaker safely and still work when the cheap tiny driver tube got replaced. It was claimed that using this tube would reduce "callback" repairs compared to the original 6JE6 type. This ad was clearly aimed at TV-repair shops.

I'm pretty sure Ed Dulaney saw this same ad and said to himself "200 Watts? I won't key a box any longer than thirty seconds!"

This was the only tube we used home-brewing base linears when I was in high school in the late 60s. Naturally hitting it that hard would reduce the life of the tube in a big way. But the practical anode rating for the upgraded tube was closer to 50 Watts, if you didn't key for more than a minute or so straight.

Along the way the original 6JE6 tube was still in production. It got revised twice, with the suffix letter "A", and then later "6JE6B". Some time in the early 70s, the older 6JE6 tube's design got revised yet again, and its ratings were boosted. Still had the skinny anode wire and hollow brass plate cap held in place with glue. But they gave it a suffix letter "C", to indicate it was the third upgrade of the design. Now you could brand a tube "6LQ6/6JE6C" even though it was still the old, wimpy design. Seemed kinda dishonest to me, but that's politics.

The upgraded tube with the dual strap leading from the anode to the black plate cap received a new JEDEC number. (Joint Electron Device Engineering Council).

The stouter version of the original 6JE6 was thereafter called the "6MJ6".

Can't remember the year of the changeover. Probably 1973 or 1974.

So, the meaning of that type number "6LQ6" depends on when the tube was made, as much as it does what's inside.

Gotta find that magazine ad.

73
 
  • Like
Reactions: Dr_DX, Jay Mojave, Shadetree Mechanic and 1 other person
nomadradio said:
The original 6JE6 tube was used in RCA's large-screen (21-inch and 23-inch) color TV models of the 60s. These sets had a failure problem in the field. If the drive signal to the tube failed, it would immediately overheat. The bias voltage that controlled the tube's current was derived entirely from the drive pulse feeding into it.

The result was that if the tiny 6GH8 tube driving it were to shut down for any reason, the tube would cherry, melt the glass and blow out the expensive horizontal-output (flyback) transformer as well.

Bad news was that this kept occurring to sets under warranty. There were some house fires that got news coverage at the time.

RCA came up with a couple of fixes for this. First was to design a special circuit breaker with two inputs. The normal side was in line with the AC line cord. A second element went from the cathode of the horizontal-output tube to ground. If that tube lost its drive, it was supposed to draw enough cathode current to safely trip the breaker.

Safely, maybe. But not for the tube. The new breaker would protect the TV owner's house but not the horizontal-output tube.

Around 1968 or so RCA redesigned the 6JE6 with thicker high-temperature glass that wouldn't soften as easily, a heavier anode, and a "hard-seal" plate cap that had a black coating. Pretty sure the coating was to make it bond to the glass. The previous tube had only a thin wire from the anode, through the glass and soldered to a hollow brass plate cap glued to the envelope. This "black" plate cap was bonded to the harder glass around its entire 3/8-inch outside diameter.

I'm still looking for a copy of the advertisement I saw in Popular Electronics when the new, beefier "6LQ6" tube was introduced. The claim was that the anode would dissipate 200 Watts for 30 seconds without damage. Now RCA had a tube that would pop that dual circuit breaker safely and still work when the cheap tiny driver tube got replaced. It was claimed that using this tube would reduce "callback" repairs compared to the original 6JE6 type. This ad was clearly aimed at TV-repair shops.

I'm pretty sure Ed Dulaney saw this same ad and said to himself "200 Watts? I won't key a box any longer than thirty seconds!"

This was the only tube we used home-brewing base linears when I was in high school in the late 60s. Naturally hitting it that hard would reduce the life of the tube in a big way. But the practical anode rating for the upgraded tube was closer to 50 Watts, if you didn't key for more than a minute or so straight.

Along the way the original 6JE6 tube was still in production. It got revised twice, with the suffix letter "A", and then later "6JE6B". Some time in the early 70s, the older 6JE6 tube's design got revised yet again, and its ratings were boosted. Still had the skinny anode wire and hollow brass plate cap held in place with glue. But they gave it a suffix letter "C", to indicate it was the third upgrade of the design. Now you could brand a tube "6LQ6/6JE6C" even though it was still the old, wimpy design. Seemed kinda dishonest to me, but that's politics.

The upgraded tube with the dual strap leading from the anode to the black plate cap received a new JEDEC number. (Joint Electron Device Engineering Council).

The stouter version of the original 6JE6 was thereafter called the "6MJ6".

Can't remember the year of the changeover. Probably 1973 or 1974.

So, the meaning of that type number "6LQ6" depends on when the tube was made, as much as it does what's inside.

Gotta find that magazine ad.

73
Click to expand...
"And now you know the rest of the story."… Good Day!
 
Last edited:
  • Like
Reactions: Shadetree Mechanic

dxChat
Help Users
  • No one is chatting at the moment.
  • dxBot:
    Greg T has left the room.
  • @ BJ radionut:
  • @ BJ radionut:
    EVAN/Crawdad :love: ...runna pile-up on 6m SSB(y) W4AXW in the air
     +1
  • @ Crawdad:
    One of the few times my tiny station gets heard on 6m!:D
  • @ Galanary:
    anyone out here familiar with the Icom IC-7300 mods


      Top Bottom
      Back