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    Increasing Time Delay Relay Board Timeout ?

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    arledgsc

    Posts: 229
    Join date: 2012-11-30
    Location: SF Bay CA

    Increasing Time Delay Relay Board Timeout ?

    Post by arledgsc on Fri Jun 21, 2013 3:21 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
    Admin

    Posts: 1970
    Join date: 2008-11-26
    Location: Massachusetts

    Re: Increasing Time Delay Relay Board Timeout ?

    Post by Bob Latino on Fri Jun 21, 2013 4:20 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: 229
    Join date: 2012-11-30
    Location: SF Bay CA

    Re: Increasing Time Delay Relay Board Timeout ?

    Post by arledgsc on Sat Jun 22, 2013 9:35 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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