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Increasing Time Delay Relay Board Timeout ?

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arledgsc

Posts: 224
Join date: 2012-11-30
Location: SF Bay CA

Increasing Time Delay Relay Board Timeout ?

Post by arledgsc on Fri Jun 21, 2013 2:21 pm

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

Bob Latino
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Posts: 1955
Join date: 2008-11-26
Location: Massachusetts

Re: Increasing Time Delay Relay Board Timeout ?

Post by Bob Latino on Fri Jun 21, 2013 3:20 pm


Hi Scott,
 
 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)
 
Bob


arledgsc

Posts: 224
Join date: 2012-11-30
Location: SF Bay CA

Re: Increasing Time Delay Relay Board Timeout ?

Post by arledgsc on Sat Jun 22, 2013 8:35 am

Thanks Bob.  I put in a 1M ohm resistor last night and get about 40 sec. delay which is perfect.  Scott
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