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This is (my) version. I took all the voltages to help anybody who has an original or copy with a fault. The voltages should be close enough on most versions but the pin numbers will NOT be. I also changed most of the components to suit what I have, being too mean to buy anything. I also have a separate TUNE switch for the same reason. In this version -5 is from a voltage convertor. A CMOS 555 flashes a low current LED with the battery falls to around 6v. My board is removable with ease because everything is on connectors which you will see in the drawing. I found why it was so rubbish last year when I first tried it - I had a diode the wrong way round, which I discovered when taking these voltages. Where I indicate a changing voltage, this will be something triggered by noise as there is nothing 'running'. When fault finding you really need to be somewhere close to this before you hook up the coil. Quiescent current should be fairly close to (my) 21mA if the battery life is to be as claimed - but you may find a difference here - if it is more than say 50mA, you have a problem.
Hope this is of use.