HMV 902. Replace EHT transformer.

[bobhowe]

Hi David back on topic very wise to make a lid to stop as you say keep prying fingers out kind regards Bob

[Geordie McBoyne]

Yesterday, the power supply unit was reinstalled in the HMV 902. Those EHT components really do look rather exposed! At least the U16 rectifier valve has an insulated top cap.
A box must be made to contain the EHT transformer and valve. The HT rectifier valve and smoothing choke will have to be repositioned to make space for the box.

Geordie McBoyne.

[peter scott]

Your "new" EHT transformer looks great. I hope it won't take a lot more work to get the 902 up and running again.

Peter

[Geordie McBoyne]

HI Peter,
a box having the same dimensions as in the 900 can be made using 0.8mm steel plate. However, the HT rectifier valveholder will have to be moved about 12mm from it's present position.

Geordie McBoyne.

[peter scott]

Nothing is ever simple.

Peter

[Murphyv310]

Hi.
The box as drawn no doubt fouls the EHT rectifier. Could you not reshape the box to give more clearance? Surely an easier task than having an extra hole in the chassis!

[Geordie McBoyne]

Rather than relocate the HT rectifier valveholder the EHT transformer has been moved closer to the rear edge of the chassis. The adaptor plate has been retained and cut down to 4 1/4 inches wide. Now it will be possible to make a screening box to the dimensions as the original part.

Geordie McBoyne.

[Mike Watterson]

That does/will look better.

[Geordie McBoyne]

The power unit has been reinstalled in the HMV 902. Will report how well the set performs later today.

Geordie McBoyne.

[Geordie McBoyne]

No results today, the TRF unit needs attention. The attachment shows the interior of the HMV 902. The CRT and optics are similar to the Marconi 701.

Geordie McBoyne.