Increasing Time Delay Relay Board Timeout ?
- Posts: 256
Join date: 2012-11-30
Location: SF Bay CA
I searched on the forum but did not see any information. I have some old tubes and I would like to increase the timeout to 30 sec as their datasheets claim it takes 23 sec. to warm up the cathodes. I assume it is a 555 timer type chip onboard but what is actualy chip on the TDR board and is the cycle time governed by the resistor/ cap off of pin 6? And what are the 17 sec. timeout default values for the resistor and cap? Sorry for being lazy but I cannot find any setup info. Thanks, Scott
- Posts: 2095
Join date: 2008-11-26
In the manual for the VTA TDR are given the following other time delays you can use ..
NOTE - The time delay may be altered by changing out R3. R3 as delivered with the kit is a 470K (470,000) ohm resistor and gives a 17 second time delay.
270 K = 10 second time delay (resistor not supplied with kit)
470 K = 17 second time delay
750 K = 27 second time delay (resistor not supplied with kit)
1 meg = 36 second time delay (resistor not supplied with kit)