[Amps] Transformer Noise

[Ian White, G3SEK]

John wrote:
>Hi
> I have three amps ....SB200 , SB1000, Dentron Clipperton L ..... They all
>work fine ,But the SB1000 & Clipperton both have Transformer Buzz & hum. The
>SB200 transformer is  super quiet ..... Why is that ??  What is heathkit
>doing that the other are not ?? Can I do anything about it......

In the SB-1K, more than half the noise seems to be coming from the steel 
cover, vibrating in the stray magnetic field. Changing to a non-ferrous 
cover would probably help.

-- 
73 from Ian G3SEK         'In Practice' columnist for RadCom (RSGB)
                            Editor, 'The VHF/UHF DX Book'
http://www.ifwtech.co.uk/g3sek