[time-nuts] 50 ohm driver

Hal Murray hmurray at megapathdsl.net
Thu Mar 5 21:55:56 EST 2015

martyn at ptsyst.com said:
> BTW, the reason he wants this high voltage is because he is driving a very
> long cable from the distribution amp to the actual receiver.  

If you have a long cable, the rise time at the driver isn't critical.  It 
will get filtered out by the cable.

Of course, how long is long?  Here are some scope pictures for 100 ft of 
coax.  The driver is a TBolt.  I forget what chip they use.

If you are going to redesign the board and prefer chips to transistors, check 
out the bus driver chips.  They typically come 8 drivers to a package.  There 
used to be some with 16.  There were also some chips that included a 25 ohm 
resister.  They were intended for driving memory busses.

These are my opinions.  I hate spam.

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