[Amps] Fizzing From Amp

[Ian White GM3SEK]

Adrian Rees (M1LCR) wrote:
>Hi all
>My Dentron ML2500 has just started making interesting "Fizzing" noises.
>This appears to be from the Tune + Load Caps, and happens whenever I Tune
>Up, or on air.
>
>The amp is putting out its usual power, but I wonder if its a build up of
>dust and Nicotine on the Cap Plates that is causing this.
>
>(The nicotine from our chain smoking contest ops)

Nicotine - or rather, the tar deposits - can be very bad for switches, 
variable capacitors and other contact surfaces. Amplifiers can be 
particularly bad, because the fan collects hours and years of smoke and 
pushes it through the insides.

Having once cleaned out an SB-220 for a friend who was a heavy smoker, I 
wouldn't ever do it again - not for anybody. It was absolutely 
disgusting: the insides were plastered with a mixture of house-dust and 
sticky tar, and the inserts on the control knobs were not silver 
coloured: they were gold. Aerosol foaming cleaner would shift it, but 
the whole job took a can-and-a half of cleaner, two whole kitchen 
rolls... and a long, long shower afterwards.

Take a look inside the amp: if that really is the problem, make THEM 
clean it out!

Sadly my friend is now SK, from... yes, you guessed. Aerosol cleaner 
only works on amps, not inside people  :-(


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