Date: Sat, 20 Feb 2010 09:56:54 -0600
From: "Cecil Acuff" <chacuff@cableone.net>
Subject: [Amps] Hotswitching issues 30s-1
Hi Folks,
I am having a problem with my solid state rig switching to TX and outputing
RF quicker than the amp is ready to process it.
I have considered taking the key line to an external box that activates the
amp key line prior to sending PTT to the rig. Would work great for SSB but
not sure so good for CW.
Am I making this harder than it should be?
&&& YES. It`s a real simple fix.
My FT-1000MKIV is giving me a high SWR display because of the few
milliseconds of no load while waiting for the open frame relay in the
Collins to get in place. Once all is settled the reflected power is nil...
&&& I use a P+B opto isolator on the output of both my MK-V`s
(ODC-15) is rated for 9-18 vdc input at 15 ma. Output side of it is
rated at 60 vdc at 3A CCS. (ODC-15A) is rated for 9-18 vdc input at
15 ma.Output side is rated for 200 Vdc at 1A CCS. The input to output
isolation is a whopping 4 kv. The 13.8 vdc to operate em is available on
the band data jack on the MK-V. The GRND that actually operates them,
comes from the same band data jack..Electronic grnd.
(internal yaesu switch transistor) The stock yaesu spst mech relay is SHUT
OFF, no longer used ! It`s useless anyway, since it takes 15 msecs to
operate (which just adds ANOTHER 15 msecs to ur already slow
collins relay). The P+B ODC-15 and A version... will operate in 100
microseconds. The release time on both opto`s is 750 microseconds.
No more hot switching ur collins on SSB.
&&& the MK-V, in the menu.. for ``QSK`` has ADJUSTABLE 0-30 Msec
DIGITAL delay for CW only ! This feature allows the external amp to be
keyed..NOW... but RF does not come out of the MK-V for up to 30 msecs !
It does not truncate and dots +dash`s either. Being a digital delay,it`s like
a buffer. You key the paddles in real time, but RF is delay by 0-30 msecs.
This one feature alone in the MK-V will give ur collins a 30 msec
HEAD START. This feature is for CW only.
&&& I set mine for 30 msecs. I also use the P+B ( also made by opto22,
both available from Mouser)ODC-15A to key the vac relay`s in the HB amp
(which use a +120 vdc speed up voltage).. and also use em to key the
TR mech relay in the Drake L4B`s. As a side note, I converted the half wave
rectifier in the L4B. (+27 vdc relay supply) to a FWD.. = +63 vdc.
One 3 watt mof in one leg of the stock mech drake TR relay coil,and the
mech relay is WAY faster, still not qsk though.. just faster VOX ssb + CW.
&&& You could also simply install a Gigavac GH-1 vac relay, etc, in the
30S1. The Gh-1 will operate in<2 msecs. BTW, the excellent GH-1 is
available in 12 vdc coil.. + also 26.5 vdc coil. The 12 vdc coil version
can easily be sped up with just 24+ vdc applied to it.. and correct drop
resistor.
later... Jim VE7RF
Don't want to blow up the rig...
Don't have this problem with my old Dentron Clipperton L...I guess it has a
faster relay.
Thanks...
Cecil Acuff
K5DL
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