08-01-2013, 06:13 PM
(This post was last modified: 08-01-2013, 06:26 PM by Radio Fixer.)
I reckon 46 swg will way be too fine David. Just mic it and take off a bit for the insulation and look it up. My 40,000 (4.5 miles) turn field used 38 swg. Look back to Bulletins in 2003 for my coil winder and coil winding articles. I did wind a transformer with it of 15,000 turns (3 wdgs) using 42 swg without a break. Its possible to work out how many turns from the weight of the former once you have it off, less a bit say 10% for the former.
But if it comes out 10 or even 20% low its no problem as field stength makes no difference to quality and only a marginal difference to volume. Try it for your self if you have a field coil speaker and a variable power supply for the field. If it comes out high by a similar amount you will drop a bit on HT but if you are bothered or it runs a bit hot just shunt it down to the appropiate value with an external resistor. Aim for it to come out low R and turns is better.
Well I used to think like you Robert and 'once upon a time' Chas Miller said to me "The trouble with old radios is there are just too many of them. People put them in the loft. If there were less of them those left might be valued more". A the time, full of enthusiam I thought it very odd. But now having done my share of basket cases I understand. If I'm going to spend a lot of time and probably a fair sum of money its better to do it for something thats rare, or has good looks and can be made to look really beautiful (an advantage of wood over Bakelite) when standing on someones sideboard. Preferably I now go for all 3. Once us old boys (and I dont include you as you look younger than most) have gone there's going to be so many radio sets around that only those in that state are likely to find a warm home.
I could write more but dinner calls
Gary
But if it comes out 10 or even 20% low its no problem as field stength makes no difference to quality and only a marginal difference to volume. Try it for your self if you have a field coil speaker and a variable power supply for the field. If it comes out high by a similar amount you will drop a bit on HT but if you are bothered or it runs a bit hot just shunt it down to the appropiate value with an external resistor. Aim for it to come out low R and turns is better.
Well I used to think like you Robert and 'once upon a time' Chas Miller said to me "The trouble with old radios is there are just too many of them. People put them in the loft. If there were less of them those left might be valued more". A the time, full of enthusiam I thought it very odd. But now having done my share of basket cases I understand. If I'm going to spend a lot of time and probably a fair sum of money its better to do it for something thats rare, or has good looks and can be made to look really beautiful (an advantage of wood over Bakelite) when standing on someones sideboard. Preferably I now go for all 3. Once us old boys (and I dont include you as you look younger than most) have gone there's going to be so many radio sets around that only those in that state are likely to find a warm home.
I could write more but dinner calls
Gary
