Keying SB220 with Mark V
Problem: Just began the connections to a new
MK V and find that the 120VDC from the relay in the SB220 amplifier is not
compatible with the MK V relay which is good for only 100VAC or 60VDC. However,
the manual states it is compatible with the 220 and 221 in the instructions for
hooking up a linear amp. Anyone know the real deal here? I do now wish to fry
the internal XCVR relay but also do not relish the thought of adding another
external relay just to drove the SB-220 relay.
Al, N6TA
Solution 1: You can order a kit from Haubach
Electronics or an external interface from the HeathKit Shop
http://www.theheathkitshop.com/ampkeyer.html
Solution 2: Best to use the Band data connector
to key the 99, and disable the relay switch on the back. No clicking and super
fast and smooth QSK. Pin 2 and 3 to amp PTT and ground pin 8 permanently. 73
Saad N5FF
Solution 3:You should buffer the puny PTT
from the MP's band data plug, or risk de-smoking things. K6XX goes into this in
detail here:
http://www.k6xx.com/radio/mpbandbx.html Blake N4GI
Solution 4: The following link may be
helpful:
http://www.qsl.net/icom/auxrelay.html Whilst applicable mainly to Icom
radios, this page contains some useful general information on keying tube
amplifiers from a transceiver. Adam VA7OJ/AB4OJ