Restoration Project

[iw5ci]

I got another Art-13 on Epay...
Really not in bad shape and complete of tubes.
The previous owner never did an ht power supply. He told me that he had modified the BF module with a micro amplifier and removed the switch for carbon/dynamic micro .
He told me he has tested the BF module supplying the 400V tension and picking up the bf from the plate of the 811 and listening to the bf with a proper transformer.
I have connected the power supply of my actual art-13 to the new one and the autotune work perfectly, also the rf and multipliers stage work good! i have a nice 80W output with 900v of HT, but i have no modulation.
I put the bf module of my working art-13 in the new one and it still doesn't' work. I also put the bf module of the new art-13 in the old and woring one and no BF. what you suggest to do to make some simple tests?
the modulation trasformer is OK, i read the same resistance value from all the pins of the trasformer in both art-13
Any help will be really useful.

[W3RSW]

I cannot help you with your problem much but I am very impressed with that crystal control unit.  -Pan American Airways.-  That sure brings back nostalgic memories.  You have a nice collectors item there.  Great find.

[KA0HCP]

Hello Andrea, you have found another interesting project!

Since you have the advantage of another working model, it seem like the best approach would be to compare the two modules component by component to look for any modifications.

73, bill

[iw5ci]

Job done

First photo: the art-13 just arrived in the shack
Second photo : after cleaning, repainting and detailing.

Video of the art-13 after electric repair , 95w in 80 meters with only 900 volts hv.

http://youtu.be/Khf5zL3ckME

The marvellous auto tuning in action:

http://youtu.be/5bk4vl7dva0

[W1AEX]

Nice clean up job! Looks like a beauty!