A lot of discussion going around whether the 318 is required for this
configuration, or that amp, etc.
What the 318 provides, is a way for you to increase how long the amp key
line is held in transmit before going back to receive.
The main reason for this is for people who want to drive big amps and don't
want to work their amp relays to death in and out of transmit.
Whether your amp REQUIRES this type of interface is really up to the
However, I do know several that are happy to see this now because it gives
them a chance to help save their amp relays long term.
It is a great addition to a radio that does not provide a true amp key
The 318 is configurable for the amount of delay delay in releasing the amp
key line back to receive from 100ms to 2 seconds. This is sufficient for
anyone who wants to protect his amp but doesn't necessarily need QSK in
high speed CW.
We added a few neat little helper features such as PTT button on it to
force a key of the amp while you are tuning or other activities. Output
polarity jumpers, phono jack that can be used as a footswitch, etc.
With the pinouts, it can be adapted to almost any amp rig combination on
the market. (granted, I'm sure some of you will find some that it won't
work with, but that would be a rig that doesn't provide an amp key output
line, and who knows what else is out there.)
The Din Connectors are made so that you can Daisy chain several accessories
together, and only use the 318 delay when so desired.
It is configurable internally with jumpers for positive active transmit or
negative active transmit, regardless of what your input transmit control
line polarity is. It will accept +4VDC to +24VDC on the input transmit
It's based on a circuit used by a couple of TenTec employees for several
years, with a few added configurable items to work with varying amp and rig
To answer the questions: "Is this required in my current setup?" That
answer should be obvious, no. If your current setup is working, there is no
need. However, if you want to help improve the life of your amps relays or
find a setup that you NEED the amp key line held longer than your rig
supports, then this is a great little gadget that proves this, and a bit
Me? I'd get one to use when running a kw or more amp and I want to preserve
relays when using CW. Just my two cents.
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