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Electrical Contractors Licence No 71364     

ABN 91771621084

2017    BOWMAC  Electrical

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Bowmac Electrical

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Grundig 4090 Back Panel
Grundig 4090 behind dial glass
Grundig 4090 Filter cap and Rectifier
Grundig 4090 Illumination
Grundig Front Face
Grundig 4090 under chassis
Grundig 4090 Recapped
Grundig 4090 AM FM dial string
Grundig 4090 Top Chassis
Grundig 4090 Chassis
Ferrite Antenna string and indicator
Grundig inside back

Grundig Majestic 4090 AM/FM/SW

Grundig Majestic USA 4090 (1956/7), was brought to me as a customer repair, and like always I tested the valves and found 3 to be faulty. Then onto the capacitors, I did however leave the dual 100uf can capacitor to see how that would fair up, no good. After changing all the polyester and Electrolytic caps I slowly wound up the voltage on my variable transformer to hear a noisey shuttering from the bridge rectifier. I did run it for about a minute and shut off the power and the rectifier (B250 C75) was very hot. After a quick trip to the electronic store I fitted a new bridge rectifier and also fitted a 

100ohm 10 watt resistor from the +, in series to the filter capacitors (below). The Fm and the Ferrite Strings were broken and I had very little string left to go on, only the AM stage was still in tact. What really stumped me was how did the FM string work with the AM string, well that crossed my mind, after looking at a video on Y.T I realised the FM dial pointer was missing so I had to make one up from perspex, then I sat for some time figuring out the stringing for the FM. Then the ferrite antenna had to be strung, after many attempts

I finally figured out the antenna slewing. The tuning eye also needed to be replaced as it was also faulty. This set has 4 speakers wired in series and has a fantastic sound, it is very bassy and has an equalizer. The ferrite indicator has a light inside which is operated by the FA switch.

Hope these picture maybe useful. 

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