Since I'm not familiar with how the Alpha handles the
keying signals, that part will have to be settled, but the
TenTec is quite straight forward.
A dc voltage is applied to the "TXOUT" with every dot or dash
and follows the keyer input exactly. However, the OMNI will not
transmit until a dc voltage appears at the "TXEN" jack.
So - with what you're saying, the Alpha is sending a dc voltage
back to the Omni. Not good! I assume your Alpha uses
vacuum relays for switching. If so, you need to find out why
it is sending the dc voltage on the TXEN line and rectify it.
However, if you're using pin diode switching in the Alpha, then
all you need to do is to jumper the "TXOUT", the "TXEN" and the
keying input to the Apha and eliminate the return line to the
The only reason for the return voltage is to eliminate :Hot-Switching"
relays while rf is applied.
From: Jim Reid <email@example.com>
To: Ten-Tec, Inc., Amateur Radio Sales <firstname.lastname@example.org>;
email@example.com <firstname.lastname@example.org>; w6ru <email@example.com>;
Paul Christensen <firstname.lastname@example.org>
Date: Sunday, September 20, 1998 9:34 AM
Subject: [TenTec] Omni QSK with Alpha's 87A QSK
>Aloha from Kauai,
>To Scott and the bunch at Ten Tec, and the guys here
>on the reflector who have already commented to me
>on this topic.
>Problem restated for the guys at Ten Tec:
>Ok, I cannot get the VI+ and the 87A to do their thing. I have
>tried using the 87A in the keying loop a la Ten Tec linears.
>The result, whenever the rig is on, it is transmitting!! I
>connect the Omni TX Out to the 87A relay in; and the
>87A "c" key output back to the Omni TR EN. And it
>is keyed continually ON, no matter what state the
>87A is in; Standby or Operate. There is no response
>of any sort from the 87A, other than it indicates RF
>power passing through, but, if the Omni is on 20 CW,
>and the 87 was last on 40, that's where the 87 stays.
>So the indication from the Omni to the 87 is not taking.
>When the RF output is continuous from the Omni, and I
>press the CW key, the sidetone appears and follows
>the key, but the RF out is constant.
>>From what I read about
>the Omni Control Board on pg.. 4-16 in my manual, this
>should work, I think. The manual text says, "the Logic
>board generates a transmit acknowledge voltage at
>connector 63. This drives Q11 which sends the key
>signal over to the Relay on the 87A, as I read it. Then
>the 87A would send the key signal back into the Omni
>TX EN connector, and we should be off and running.
>On the Corsair II, I connected my key signal directly to
>the 87A Relay input; and then keyed back to the
>Corsair II key input from the "c" key output of the 87A;
>that seemed to work fine. Again, tried this with the
>Omni, and it didn't work either.
>I now have had several QSO's: JA, EA, OE, 5V7, SP, DL,
>I, and KC4 down at the South Pole. However, I am using
>the mechanical relay in the Omni to talk to the 87A relay
>input line -- which is driving me nuts with its "clacking".
>That's why I sold the foreign rigs and bought the Omni,
>was to achieve fabulous QSK. But it is not happening.
>There is no way, with my eyes, for me to even begin to
>think of performing the mod Paul, W9AC, has suggested.
>By pass the LCO relay, change the xistor, and key the
>Alpha with the former relay key signal.
>I bought the OmniVI+ especially and specifically for the QSK
>feature, and having had no trouble using QSK of the Corsair II
>with my 87A, presumed this would be duck soup with the
>newer design and better rcvr Omni. Now I am really unhappy!
>I specifically mentioned the 87A in my order to Ten Tec; Scott
>responded with the comment that it was just a matter of connecting
>up RCA jacks, and all would be well. Well I have tried the connections
>for the Ten Tec QSK linears in the manual, and that does not
>seem to work with the 87A, unless there is something obvious
>I have yet to notice.
>However, Jim, W5ODD, has emailed that he has had the same
>experience with his 87A, that is, no QSK ability! And Walt, K8CV,
>sent the following:
> "You probably have it figured out by now, but, when you key the 87
>and it keys the Omni you need to put the jumper plug back in on the
>in and out key thing. From the linear to the Omni is just 2 wire to
>the key ( rca ) jack in. I have never done this but, if you want to
>use the INTERNAL keyer on the Omni then you need the in and out
>thing! With an external keyer just key the amp and let it key the
>rig. Works for me!".
>This sounds as if it is exactly the same set up I used to have QSK with the
>Corsair II and the 87A. Not completely sure I
>understand Walt's input.
>Anyway, in the several years now that both the 87A and the Omni's
>of various generations have been on the market, I have to
>believe someone, and especially someone at Ten Tec
>must know how to set this up in some rather straight forward
>manner so one can have the QSK features of both the Omni
>and the 87A, and also be able to use the Omni with the 87A
>for the occasional SSB QSO. It would seem with the Corsair
>and Walt's solution, you have the 87 available only for CW, unless
>you lock the CW key down when you want to transmit SSB in order
>to tell the amplifier to operate, hi.
>Am sorry to have bumped into this problem within the first
>36 hours of owning the Omni. Sure hope someone on the
>reflector, or at Ten Tec, can come up with the needed
>solution. Not sure I will keep the Omni if this cannot be
>resolved, as that was the principal reason I bought it.
>It is, obviously, in warranty, and for me, this is a warranted
>feature of the Omni, QSK computability with QSK capable
>commercial linears. The only caveat in the Ten Tec manual
>for needing to use the LCO Control Board K1 relay is when
>one is using a non-QSK capable linear (see note on the
>linear of the OmniVI+ manual Fig. 1-10, pg. 1-7.) The
>Alpha 87A is certainly QSK capable!
>73, Jim, KH7M
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