Not a lot of responses to my query about open frame relays but I will pass
what info I received.
1. Use Dow Key relays (remember the 1 inch square about 3 inch long ones of
yester year?)
2. Use vacuum relays
3. RTE24012F by Potter Brumfield
4. RKS-5DW-12 by Potte Brumfield
5. W389CX-7 by Magnecraft.
If I remember correctly #4 was used by DX Engineering in their antenna
switch boxes.
Vacuum relays are always good ro protect contacts from weather plus other
benefits.
My use is intended to switch between antennas in a yagi stack on 10, 15, and
20M. Starting with 10M and I want to be VERY conservative in ratings.
Design for 3KW+ and use at 1.5KW max ( and factor in some SWR). No hot
switching unless I for get (I hope not).
Comments/Suggestions received:
Use DPDT and parallel contacts for higher cureent rating.
No wx problems with vacuum relays.
Open frame relays have immeasureable loss at HF.
Voltage rating (insulation) is biggest concern. (1500W into 50ohms is about
275 volts with NO SWR)
Because the W389CX-7 is rated for 1HP 600VAC motor control this may be the
best suggrestion short of vacuum relays.
Hope this info helps others with interest. If I build it they (the DX) will
come I hope.
What relays are in the highly rated RCS-8V?
73 de Arne N7KA
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