[Amps] GS-35B on 6 meters

[Ian White GM3SEK]

Bill Turner wrote:
>I wondered about this. Why connect to the cooling fins when you can 
>easily connect directly to the anode itself? I just made the connection 
>to a lug under the screw that holds the fins on and so far, so good.
>
>I haven't had it on the air yet, but into a dummy load it does fine. 
>Hope to have it on the air in the next week or so.
>
People do that... but just because you can remove the anode cooler of a 
GS35/31 or GI-7, that doesn't make it a good idea.

Remember that up to 1500W of heat has to flow through the interface 
between the flat top of the external anode, and the flat bottom of the 
anode cooler.

That interface is like bolting a huge power transistor onto a small 
'dry' heatsink. Even the tiniest gaps will dramatically increase the 
anode seal temperature... and the factory machining on those two 
surfaces is already quite poor.

When you insert a sheet metal lug between the anode and the cooler, that 
lug will have been distorted by all the drilling and shearing you've had 
to do. Unless you make the lug from copper, and very carefully lap both 
sides flat again, there will be gaps and there could be trouble.

The only good reason to remove one of those coolers would be to take the 
rough spots off the existing surfaces - and then put it right back on 
again.



-- 
73 from Ian GM3SEK         'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek