27-10-2020, 09:00 PM
(This post was last modified: 27-10-2020, 09:04 PM by Murphyv310.)
Thanks Amie.
Looking at the Micromatic circuit we see that to keep the component count down even TR2 uses simple dc feedback bias between base & collector. C5 too is providing AC negative feedback at higher frequencies so giving some bass boost, great for those toppy piezo earpieces.
Don't forget at that time there was a lot of experimentation to get the best results no PC programs to aid design and circuit parameters.
The way L1 and L2 are wound is unusual, it helps with matching and the Q of the the two windings I believe.
I'll need to get back to the rod pentode radio over the winter but sadly I need to use decent magnifier these days, too many years fixing radios and TVs with all this close work.
PS Manx coming in quite well on the little set, doubt I'll get Caroline on it but it's quite receivable here so long as selectivity is good.
Looking at the Micromatic circuit we see that to keep the component count down even TR2 uses simple dc feedback bias between base & collector. C5 too is providing AC negative feedback at higher frequencies so giving some bass boost, great for those toppy piezo earpieces.
Don't forget at that time there was a lot of experimentation to get the best results no PC programs to aid design and circuit parameters.
The way L1 and L2 are wound is unusual, it helps with matching and the Q of the the two windings I believe.
I'll need to get back to the rod pentode radio over the winter but sadly I need to use decent magnifier these days, too many years fixing radios and TVs with all this close work.
PS Manx coming in quite well on the little set, doubt I'll get Caroline on it but it's quite receivable here so long as selectivity is good.
