[Amps] HL2K question

[Patrick Egloff]

Hi all !

A friend of mine gave me a Tokyo High Power HL2K amplifier (serial # 603456)
. Of course, it did not work anymore.... :-)

After reparing all the problems (HV transformer leaking, HV caps, fan + fan
relay, different output Pi caps, bias circuit) , cleaning all the switch
contacts and changing the tubes, it is now running normaly and is very
stable. Well, i should say, more or less normaly !

Indeed, i noticed something weird around the output coil. At first, i was
testing the amplifier with the bottom cover removed so i could access to the
caps and coils.
When i mounted this cover for a final check before puting this amp in
service, i noticed an output power drop on all lower bands but more
noticeable on 80 and 160m. On 80m it dropped from 1,1kW to 950W and on 160m
from 1kW to 800W ! Tuning is very "blur" on 160m.

I also noticed that the cabinet around the coil was getting really warm.
When running at full power and sliding the cover to move it closer to the
coil to its normal position, i see some small sparks between the cover and
cabinet and feel some "tinglings" in the fingers.

This ouput coil is less than 1cm (0.39 inch) on all its length from the
cabinet and 1,5cm (0.59 inch) on all its length from the cover ! I think
this is far to close...

Has anyone a HL2K and experienced the same problem ? Maybe more recent
serial numbers have a different layout ?

Except moving the coil a bit further from the cabinet and cover (not easy in
a commercial amp), i don't see how i can solve this problem.. Any idea ?
What would be a "good" distance ??

73, Patrick

-- 
Patrick Egloff - TK5EP
email : pegloff at gmail.com
Web page : http://tk5ep.free.fr