UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Effect of cathode strapped suppresor grid?

G6Tanuki · 19th Mar 2017, 7:25 pm

Does the Tx not have the facility to measure grid-current in the output-bottles (sometimes labelled "drive" on the meter-function switch)?

If you can't get the level of grid-current you need then the driver's at fault.

if you can get the specified grid-current but there's not enough RF coming out then the output bottles are 'tired'.

Must admit, a lot of rigs using TV 'sweep-tubes' as the output-bottles do tend to work them extremely hard so they have a short life.

If you're interested, a lot of good stuff on using PL519-style TV line-output valves has been written up by the Dutch ham PA0FRI: his "FRInear" amplifiers are things of intriguing beauty.

19th Mar 2017, 7:25 pm	#6
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 14,007	Re: Effect of cathode strapped suppresor grid? Does the Tx not have the facility to measure grid-current in the output-bottles (sometimes labelled "drive" on the meter-function switch)? If you can't get the level of grid-current you need then the driver's at fault. if you can get the specified grid-current but there's not enough RF coming out then the output bottles are 'tired'. Must admit, a lot of rigs using TV 'sweep-tubes' as the output-bottles do tend to work them extremely hard so they have a short life. If you're interested, a lot of good stuff on using PL519-style TV line-output valves has been written up by the Dutch ham PA0FRI: his "FRInear" amplifiers are things of intriguing beauty.