20-12-2016, 05:46 PM
(This post was last modified: 20-12-2016, 05:58 PM by Geordie McBoyne.)
News Flash! The detector valve in this set is in fact a 6SH7GT. The chassis is out of the cabinet and I discovered that the cathode bias components go to pin 3. On a 6SJ7GT pin 3 is the suppressor grid and pin 5 the cathode. In the 6SH7GT the cathode and suppressor grid are connected internally the connection goes to pins 3 and 5. The 6SH7 is an RF pentode, gm is a modest 4.9mA/V. Was also used as a video amplifier in some American TV receivers.
Successor valve is the 6AU6, B7G base.
It has been determined that the detector in the set is an anode bend type. Very high value cathode bias resistor, 22Kohms. Screen volts supplied from a potential divider of 1Megohm and 100Kohms, therefore 1/11th of the HT voltage.
From the Radiomuseum: http://www.radiomuseum.org/tubes/tube_6sh7.html
Geordie McBoyne.
Successor valve is the 6AU6, B7G base.
It has been determined that the detector in the set is an anode bend type. Very high value cathode bias resistor, 22Kohms. Screen volts supplied from a potential divider of 1Megohm and 100Kohms, therefore 1/11th of the HT voltage.
From the Radiomuseum: http://www.radiomuseum.org/tubes/tube_6sh7.html
Geordie McBoyne.
