[TenTec] AUX Keying OminiVI Plus

[DAVID HELLER]

By this extreme definition of no relays, etc. it appears to be impossible 
for a transceiver to have pure QSK since much circuitry is common to TX and 
RX.  My own experience was with separate TX and RX, in particular, a Viking 
II modified for very well-shaped grid block keying plus a Drake 2b - no 
matter what the speed a single dit was easily picked up no matter what speed 
was being sent.  Over the years I tried varied transceivers of the JA 3 and 
found all to be far inferior to the VikII + 2b both for the TX and the RX 
end and totally unsatisfactory for QSK CW- and this latter ruled them out 
for me for serious CW, and being a mostly CW op by choice it left me quite 
disillusioned with transceivers - but then I tried a Ten-Tec, a Triton for 
that matter.  As anyone on this reflector knows already, the RX and TX ends 
were excellent and the QSK was close enough to perfect as to have me sold; 
since then it's been T-T through a few upgrades, with occasional tries on 
other (foreign) makes which did not impress me.  But for the ultra-purist 
it's true that separate RX and TX circuitry can't quite be matched by shared 
circuitry of a transceiver.     K3TX
----- Original Message ----- 
From: "Ken Brown" <ken.d.brown at hawaiiantel.net>
To: "Discussion of Ten-Tec Equipment" <tentec at contesting.com>
Sent: Monday, May 28, 2007 5:52 PM
Subject: Re: [TenTec] AUX Keying OminiVI Plus


> Hi Paul and group,
>
>
>>>
>>> If the relay is fast enough, it is capable of real QSK.
> That is fine with me, however....
> That depends on your definition of QSK. There was a discussion thread
> here, probably years ago, wherein some expressed that by their own
> personal definition, to be real QSK there could not be a relay in the
> transceiver T/R switching, regardless of speed, quietness, or
> performance. I think the same person concluded that It couldn't be real
> QSK with any amplifier that used a relay. Another person stated that it
> is not true QSK unless you have a remote receiving site allowing you to
> receive DURING your own transmission without receiver overload. For my
> own purposes, hearing signals between dits at 30 WPM qualifies as QSK.
>>>
>>>
>>
>> The opto-coupler must still interface into another RF switching device. 
>> I
>> don't know of any opto-couplers capable of cleanly switching RF, let 
>> alone
>> switching at the100 watt level.
>>
>
>>
>>
>>
>> Given the repeated failures in that particular Omni VI, there's something
>> going on that's external to the radio.
>>
> Yes, and that is why I suggested an optocoupler. Then, unless you have
> enough voltage to break down the electrically isolated, optically
> coupled barrier (Which are typically rated at many hundreds or even
> thousands of volts), the Omni VI drive transistor could not be damaged.
> What intermediate circuitry you connect to the output side of the
> optocoupler  would depend on the amplifier or other devices being
> switched, so I did not go into detail there. One should always refer to
> the data sheets for all devices (including the transistor in the Omni VI
> key out circuit) used, to determine whether your interface is going to
> operate within the stated limits of voltage and current for those
> devices. The output device (photo diode, photo transistor, photo
> transistor darlington pair, etcetera) on many optocouplers may have even
> lower voltage and current ratings than the transistor in the Omni VI, so
> there is more than likely going to be more stuff needed than just the
> optocoupler.
>
> N6KB
>
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