Build another Bush DAC90 from salvaged parts.

[Geordie McBoyne]

Chassis is ready for test and alignment.

Geordie McBoyne.

[Murphyv310]

Hi David.
Nice neat job.
Are you opening a factory or are you farming out the work to China or Bob Howe?

[Geordie McBoyne]

Hi David.
Nice neat job.
Are you opening a factory or are you farming out the work to China or Bob Howe?

Hi Trevor, production will be done in-house.

Testing the radio set. Final checks confirmed there is no wiring errors. Connect up the frame aerial.
Connect to main supply, greeted with a working audio amplifier and IF amplifier.
No other activity though, the frequency changer is not working. Tried two other UCH42 triode-hexodes but still no results. No negative voltage on the triode oscillator grid. No oscillation. Connections on the valve base confirmed to be correct.
The continuity of oscillator coils is OK. Try reversing the anode winding, voila! stations coming through at last. Medium waveband performance is excellent but absolutely hopeless on the long waveband, in fact medium waveband stations are breaking through.
The IF amplifier must be aligned to the correct intermediate frequency, 465Kc/s.

Geordie McBoyne.

[bobhowe]

Hi David have to see some pictures i picture a 1000 words kind regards Bob

[bobhowe]

Hi David.
Nice neat job.
Are you opening a factory or are you farming out the work to China or Bob Howe?

Hi Trevor just seen your post would have liked to be around in the 50s and I would have probably liked to worked on these set then kind regards Bob

[Geordie McBoyne]

Hi Bob,
          the receiver is working very well. The medium waveband oscillator coil assembly has be relocated to the edge of the chassis. In the previous position it was just about impossible to gain access to adjust the oscillator coil core.  The adjustable cores allow accurate adjustment of the low frequency end of the wavebands. Never seen this circuit feature in other DAC90 sets.

Geordie McBoyne.

[bobhowe]

H David looking good as you say at least you can adjust oscillator coils one coil on the AC91 is impossible to adjust as well how did they line them up at the factory kind regards Bob