I would not directly key a 125V circuit either. In
fact the Corsair II manual specifially advises against
it. The EXT T/R section of the manual it says in part:
"One side of this switch is also at ground potential
and therefore should NOT be used to switch the 115/230
volt line"
I always use another relay as a matter of course
regardless of voltage level because it is a way to
assure DC isolation of the keying cicuit and helps to
avoid ground loops.
Duane
N9DG
--- denton <denton@oregontrail.net> wrote:
> The Corsair II...and I have one..does have a relay
> to key an amp..
> However I would use a second relay between the rig
> and the amp just to be
> sure...
> ----- Original Message -----
> From: "NJ0IP" <Rick@DJ0IP.de>
> To: <tentec@contesting.com>
> Sent: Friday, December 17, 2004 5:19 PM
> Subject: RE: [TenTec] Any issues with Corsair II -->
> SB-200 amp?
>
>
> > The SB-200 does indeed have tuned inputs (only for
> 80/40/20/15/10 meter
> > bands) and will work just fine with the Corsair II
> (from an RF standpoint)
> > on these 5 bands. The SB-200's T/R relay keys
> with -130v @0.051A., so
> > that
> > prohibits keying it with an open collector
> circuit. I can't remember if
> > the
> > Corsair II also had a relay for keying external
> amps. I think it does.
> > If
> > it does, then enable it and it will key the -120v
> just fine.
> >
> >
> >
> > I'm sure someone here can tell us if the Corsair
> II has a keying relay for
> > the amp. It will also be described in the user's
> manual if its in the
> > rig.
> >
> >
> >
> > If the Corsair does not have a relay for keying
> the external Amp, you can
> > obtain a "Soft Key" kit from Rich Measures
> (http://www.somis.org/) - I
> > think it only costs a couple of dollars. You have
> to make a slight
> > modification to the SB-200's relay to enable it to
> key with +130v instead
> > of
> > - 130v, but that's very simple to do. After
> installing this simple kit,
> > you
> > can key the amp with open collector circuitry.
> >
> >
> >
> > If you run a lot of CW, one problem you will
> probably run into over time
> > is
> > arcing and possible burning of relay contacts on
> the SB-200's T/R relay.
> > This will happen regardless of whether you are
> keying with the softkey or
> > with the Corsair's relay (assuming it has one).
> >
> >
> >
> > The combination switches to TR to transmit fast
> enough because the Corsair
> > adds enough delay to allow for this. The problem
> is, you really need to
> > add
> > some delay before the Amp's T/R relay switches
> back to RX. Otherwise you
> > will often incur the state where the relay has
> begun switching back to RX
> > when the TX signal comes again. It is unable to
> change directions fast
> > enough to settle in the TX position before RF is
> applied, and it arcs.
> > Not
> > bad the first 20 or 50 times it happens, but
> eventually it burns the relay
> > contacts enough that you incur errors. This is
> typically a failure of the
> > relay to switch the antenna back to the
> transceiver in RX mode. Easy to
> > recognize because you don't hear anything (or else
> it is very weak). In
> > this
> > case, you have to clean the relay contacts with a
> burnishing tool. This
> > is
> > easy to do, but requires pulling the cabinet off
> of the amp. How often
> > this
> > is required will depend on your amount of use of
> the amp. I found I was
> > cleaning mine every 2 or 3 months. I finally
> built my own device to allow
> > me to adjust the relay delay and was able to
> eliminate this problem. By
> > the
> > way, my device also keys the -130v so you don't
> need the softkey.
> >
> >
> >
> > Rich also sells a kit for replacing the open-frame
> relay with a vacuum
> > relay, but that costs a bit more. Once you have
> installed this mod, you
> > can
> > run full QSK with the SB-200 and the Corsair II.
> >
> >
> >
> > I also have to ask what you mean by "interface".
> >
> > There are probably all kinds of boxes available on
> the market which I am
> > unaware of.
> >
> >
> >
> > Gud luk and have fun with it.
> >
> >
> >
> > 73
> >
> > Rick
__________________________________
Do you Yahoo!?
All your favorites on one personal page ? Try My Yahoo!
http://my.yahoo.com
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|