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THE AM BULLETIN BOARD => Technical Forum => Topic started by: w3kbs on May 05, 2017, 09:40:10 PM



Title: Johnson 6&2 Thunderbolt
Post by: w3kbs on May 05, 2017, 09:40:10 PM
Hi Everyone.

I recently purchased a 6&2 Thunderbolt.
Any history or other information that will help in restoration sure would be of great help.
What are the weak points strong points etc.
Thanks in advance.

Cheers.

Bill w3kbs


Title: Re: Johnson 6&2 Thunderbolt
Post by: wa1mtz on May 06, 2017, 08:58:18 PM
Great find to get some activity up! 700w input AM linear, AB1, only 5W to drive it, so  sez the ad from Johnson.  (an SR-42/46 should drive it, or a gonset.)In 1962 it sold for $589.50  or in kit form, $ 524.50!! expensive! so they are uncommon.  73, mike, wa1mtz


Title: Re: Johnson 6&2 Thunderbolt
Post by: w3kbs on May 07, 2017, 09:07:56 AM
Hi Mike.

Thanks for the reply.
We have a 6 am net that meets every Wednesday night at 2100. 50.400
The Amp should be an interesting project.
Thanks for the info.

Bill


Title: Re: Johnson 6&2 Thunderbolt
Post by: Pete, WA2CWA on May 07, 2017, 02:22:15 PM
Roughly only about 254 made. Probably couldn't pass today's FCC regulations for purity. Never turn the bandswitch with the power on. I've had one since the early 90's. I've had it on the air a number of times but I prefer my Gonset 913A for 6 meters which has a single 4CX-250B.


Title: Re: Johnson 6&2 Thunderbolt
Post by: w3kbs on May 08, 2017, 12:26:29 AM
HI Pete.
Thanks for the info.
Would you happen to have a parts list or a factory assembly manual.
I downloaded the one from BAMA but would like to have the above.
Also a full page schematic diagram. Easier for me to read.

Thanks a million.

Bill w3kbs


Title: Re: Johnson 6&2 Thunderbolt
Post by: Pete, WA2CWA on May 08, 2017, 03:00:06 AM
I  was told by a former EF Johnson employee back in the 90's that he thought less then a half-dozen 6N2 Thunderbolt kits were ever shipped. The price differential between kit and factory-wired  units was too small to sway many VHF amateurs to buy the kit version. Never seen an assembly manual for the unit and probably never will.


Title: Re: Johnson 6&2 Thunderbolt
Post by: w3kbs on May 08, 2017, 10:56:19 AM
Hi Pete.

Thanks for the information. Just trying to collect as much info as possiable before the Amp. gets here.
I restored a Johnson Courier and it was a fun project and the Amp was really put together well.
I am looking forward to restoring this one also.

Thanks a million for your input. If you have a one page "large" schematic in pdf it sure would be a great help.

Bill
W3KBS


Title: Re: Johnson 6&2 Thunderbolt
Post by: w3kbs on May 09, 2017, 07:14:37 PM
Hi Guys.

Has anyone found a source for the 6&2 Band switch?
On initial check I can see it has a broken Periclean rotary switch.

Bill 


Title: Re: Johnson 6&2 Thunderbolt
Post by: Pete, WA2CWA on May 09, 2017, 09:30:53 PM
I didn't know it was an Athenian switch.


Title: Re: Johnson 6&2 Thunderbolt
Post by: K1JJ on May 09, 2017, 10:27:09 PM
Hi Pete.
I restored a Johnson Courier and it was a fun project and the Amp was really put together well.
Bill
W3KBS

Oh does that remind me of a story...

Back in the early 70's I worked in a radio repair shop. I was the tech who handled the amateur gear.  One day I fielded a call from a stuffy, refined ham doctor who said he was sending his Courier and would be there in 30 minutes.  I said fine, when it gets here I'll take a look at it.  He said "IT?!!"   I said yeah, I'll take a look at your Courier  then. He said "my courier is a HE - not IT."   I said whatever you wanna call it is fine with me - I'll look at it when it arrives.  After another round of confusion he got nasty and unhinged - thinking I was making fun of him. He axed to speak with the manager.

At that age I didn't know that a "courier"  was also a person - a messenger who transports goods or documents, in particular.

T


Title: Re: Johnson 6&2 Thunderbolt
Post by: KB2WIG on May 10, 2017, 01:11:22 AM


I thought it was a Ford.

klc
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