12-12-2013, 04:48 PM
Tony, I've searched the net for some early info on that arrangement but there's not much about it, it's the type of application where a patent might have been taken out possibly?
Yes regen tuning can be a pain, I have built several SW regens over the years and have always found the Hartley with screen grid control in a pentode to be the most reliable and smoothest to use.
I have never used a receiver with the diff capacitor arangement and I'm wondering how it compares.
The Pye MM that Alan's got uses that system, I wonder if any other UK manufactures used it?
The last regen I cobbled up was a regenerodyne type for use on SW, that had an RF amp and osc/mixer feeding into the regen det grid tank which tuned a 500khz band centered on a conversion frequency 3.5 Mhz, the det was operated at low anode and screen volts (approx 20v) that along with a low value of grid leak capacitor (22pf) and high value grid leak resistor (3.3m) enabled it to go in and out of regen with virtualy no discernable drift on reception of both AM and SSB.
I have also seen the diff cap being used as an RF attenuator on the aerial input to a receiver.
Lawrence.
Yes regen tuning can be a pain, I have built several SW regens over the years and have always found the Hartley with screen grid control in a pentode to be the most reliable and smoothest to use.
I have never used a receiver with the diff capacitor arangement and I'm wondering how it compares.
The Pye MM that Alan's got uses that system, I wonder if any other UK manufactures used it?
The last regen I cobbled up was a regenerodyne type for use on SW, that had an RF amp and osc/mixer feeding into the regen det grid tank which tuned a 500khz band centered on a conversion frequency 3.5 Mhz, the det was operated at low anode and screen volts (approx 20v) that along with a low value of grid leak capacitor (22pf) and high value grid leak resistor (3.3m) enabled it to go in and out of regen with virtualy no discernable drift on reception of both AM and SSB.
I have also seen the diff cap being used as an RF attenuator on the aerial input to a receiver.
Lawrence.
