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Ever Ready Sky Queen



Ever Ready Sky Queen The Ever Ready Sky Queen is a portable who's chassis is derived from 2 earlier Ever Ready Sets Model K and Model T which were table battery models with a valve lineup of DK91 or DK92 DF91 DAF91 and DL92 or DL94 with an IF of 452Khz.The Sky Queen uses the 96 series of valves DK96 DF96 DAF96 and DL96 the 96 series has heater current of 25ma unlike the 91 or 92 series with 50ma.
This is what it looked like on arrival. Note the worm holes in the case and the undamaged clear plastic handle.
(Note: Click on the images to get a full size picture).
Sky Queen Chassis View of the chassis after removal from the case. Everything is in place and no signs of any repair. The chassis was vertical mounting so not a lot of dust accumulates. To save time later on the primary of the output transformer was checked to ensure it was not open circuit. The aerial for the set is of frame construction fastened to the inside front of the case. The wires to this have to be removed before the chassis can be removed.
Underside of Chassis All original components. Note the wax capacitor can clearly be seen leaking (just above the volume control). There is no sign of the wiring being damaged so replacement was not required.
Tuning Scale The tuning scale was gently cleaned with a brush and as can be seen the knobs are original.
Right Hand side of the chassis All Decoupling Capacitors have been replaced (new capacitors are yellow).
C23 (The electrolytic was tested and found to be good so it was left in place). The wavechange switch was cleaned and the Tuning capacitor was cleaned and greesed. All the valve pins were cleaned with wire wool and the valve holder contacts cleaned. A final task before applying power was to check for short circuits on the LT and HT power cables.
Experimental Supply No1 The picture shows the first version of the supply under current test.
After casing the supply LT and HT were connected to the appropriate leads of the Radio.





Power was applied and the LT and HT currents monitored. The LT current appeared to be ok but as the valves do not glow it is a bit dificult to know if they are working. HT was checked at C23 the electrolytic and was reading 75 volts. But no sound. Applying a 1Khz signal to the center pin of volume control produced a healthy squeel from the speaker, so the 1Khz was injected on the signal input pin of the control and the squeel was now controlable with the sets own volume control which worked without any noise.
Now for the RF side. As there is very little current on the HT supply to work with the accumulated deposits on the valholder (and valve pins) was not liable to be burnt off so the valves were removed one by one and cleaned again. And the same was done to the valve holders. A high gain transistor amplifier (home built in the clear plastic box in the picture) was connected to the input pin of the volume control. On applying power again and tuning the radio a station was heard on the transistor amps speaker but not on the sets own speaker but it was quite faint.

Possibly an alignment problem?. So set realigned and sufficient improvement to enable the disconnection of the external amplifier.But the volume was not what I expected.One checking V3 (DAF96) its voltages were a bit on the low side so decided to change it.
The result was that I now had quite good volume on the sets speaker.And apart from tidying up this was the end of the electrical work.




The Case. So far I have not attempted to renovate the case but I intend to do it with a little help from someone who knows about such things.

Power Supplies: After this one I built another with a larger transformer for the HT which is capable of delivering a full 15 Ma. I am now building another version after obtaining some transformers that are capable of delivering 200ma at 90 volts as I now want to be able to power some 1930s sets which need about 140 volts. This version will be variable between 90 to 140 volts. I will add these to the site in the near future.


Circuit Sheet 1 Circuit Sheet 2




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Last updated 19.5.2006


2003-2006 © Maurice Woodhead