Re: Dansette HiFi Mk2 smoking amplifier
Okay, thanks for the pictures.
Evidently there is a need to improve some of the soldering, I guess you knew that already.
I'm still not sure what you understand as 'dead' is. Open circuit, but why / how? Anyway you have replaced them, so to move on...
There is very limited further testing you can do without measuring power on voltages. You are limited to resistance checks, so let's do a table and see if it throws anything up. I've marked up a picture with the valve pin numbers on it and re-named the valves as Vx and Vy as there is a bit of confusion re. the circuit, but the table will sort that out.
So try this,
-ve Meter lead on the Black wire capacitor terminal and measure round Vx.
Pin 1 =
Pin 2 =
Pin 7 Should be 180Ω =
Pin 8 Should be 560kΩ =
Now do Vy negative to the Black wire still.
Pin 1 =
Pin 2 =
Pin 7 Should be 180Ω =
Pin 8 Should be 560kΩ =
Now put the negative lead on the the point Ht2. Measure to
Ht1 Should be 33kΩ =
Vx Pin 9 Should be either 470kΩ or 180kΩ =
Vy Pin 9 Should be either 470kΩ or 180kΩ =
Please fill in the values you get, it will show an obvious open or short or incorrect value. Also might give you a familiarity with the test points if you do want to try with power on at another date.
Alan
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