18-11-2015, 05:31 PM
The Triode & Hexode are two completely separate valves, although interconnected and in the same bottle.
You don't say which anode you were checking but I assume it was the Hexode because touching anything in the local oscillator (Triode) section would have sent it way off tune!
The result you got suggests that the alignment of the aerial input circuit is badly out. Assuming the use of a decent aerial, I wouldn't normally expect to get this sort of improvement.
I thoroughly sympathise with the problems you are experiencing with test prods. There seems to be a trend these day to supply prods with very long uninsulated ends which have to be carefully held in place.
RS used to do a neat sprung probe which looked very much like this:
http://www.ebay.co.uk/itm/90-Banana-Plug...1243831883
They aren't very long, so you'll need a different pair for extended reach but they are ideal otherwise. If they are the same as the ones I remember, the centre wire is bent over at the end to form a hook. As seen in the picture, only the very end of the probe makes contact with anything but, by pressing the knob at the other end, the probe should extend and turn into a sprung hook about 3mm long which clips on the measuring point when you release the button, leaving you with both hands free.
The RS one was operated by sliding the sprung insulator with the thumb, which would probably be easier to use so, if anyone has got some 50 year old RS sprung probes they don't want, can I have first dibs, please?
You don't say which anode you were checking but I assume it was the Hexode because touching anything in the local oscillator (Triode) section would have sent it way off tune!
The result you got suggests that the alignment of the aerial input circuit is badly out. Assuming the use of a decent aerial, I wouldn't normally expect to get this sort of improvement.
I thoroughly sympathise with the problems you are experiencing with test prods. There seems to be a trend these day to supply prods with very long uninsulated ends which have to be carefully held in place.
RS used to do a neat sprung probe which looked very much like this:
http://www.ebay.co.uk/itm/90-Banana-Plug...1243831883
They aren't very long, so you'll need a different pair for extended reach but they are ideal otherwise. If they are the same as the ones I remember, the centre wire is bent over at the end to form a hook. As seen in the picture, only the very end of the probe makes contact with anything but, by pressing the knob at the other end, the probe should extend and turn into a sprung hook about 3mm long which clips on the measuring point when you release the button, leaving you with both hands free.
The RS one was operated by sliding the sprung insulator with the thumb, which would probably be easier to use so, if anyone has got some 50 year old RS sprung probes they don't want, can I have first dibs, please?
