[K3] clarification on VFO and 2nd Rx
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I seem to be very confused about the way VFOa and b control transmit and
want to get some clarification please. I started (in 2004) with an Yaesu FT-857 and am still using that, the way it works may well have coloured my understanding. If I may, let me describe what I understand based on that: The 857 has 2 VFOs, A & B and at any one time you can see the freq, mode etc set up on a specific VFO displayed, along with the VFO (id - a or b) that it is. If I press A/B, it switches from A to B and vice versa. If I have VFOa selected and Tx, it uses that freq & mode etc to transmit. If I have VFOb selected and Tx, it uses the settings for VFOb to transmit. It also has A=B which is slightly confusing and wrong, because it actually copies VFOa to b - as the A>B button on K3. A K3 without 2nd RX (KRX3) has 2 VFOs and each VFO can be set up to a specific frequency and mode, using certain roofing filters and DSP settings etc. You always listen and transmit using VFOa settings. To use the VFOb settings you must tap A/B, which swaps the settings between VFOa and VFOb, therefore meaning that VFOa is now using the settings that were on VFOb? And when you transmit, you're using those. When you do this, the TX and ^ (black arrow above TX) icons will show you as transmitting on VFOa? This is pretty much as per the FT-857, I just never thought of it in that way (I also think of the rig using different circuits to transmit, but I doubt now that it is). If you are working split, you transmit on the freq, mode etc., set up in VFOb - it uses VFOb for transmit. In this scenario, SPLIT, TX and v will be shown to indicate you are transmitting on VFOb? If you have the 2nd RX (KRX3) fitted and ON (SUB on), VFOb is used to control it. In other words, the KRX3 module does not have VFO circuits on it, it requires a VFO (B) to set it up etc. All the other rules above apply though? If the SUB is not on, its pretty much as first described? Can you even turn on the SUB if its not fitted and if you can, what happens? Finally, the [REV] button described on pg 15 as exchanging VFO a & b temporarily - what does that mean - while you have it pressed it swaps and if you release, they go back? If so, while you have it pressed and you Tx, does if use VFOb settings? Thank you Elecraft for making think about what is actually going on inside my rig - please now help me to think about what is going on inside my head! Hi -- Once upon a time a man whose axe was missing suspected his neighbour's son. The boy walked like a thief, looked like a thief, and spoke like a thief. But the man found his axe while digging in the valley, and the next time he saw his neighbour's son, the boy walked, looked and spoke like any other child. -Lao-tzu, philosopher (6th century BCE) _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: [K3] clarification on VFO and 2nd Rx
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David,
It may help if you mentally divorce the physical VFOs from the A and B designations and think of the DISPLAYED frequencies. The main receiver will receive on whatever frequency is displayed on the VFO A readout, the sub-receiver (if installed) will receive on whatever frequency is displayed on VFO B. When SPLIT is active, the above conditions are still true. In SPLIT, transmit will take place on the frequency that is shown in the VFO B display. How you alter the frequencies between the VFO A and VFO B is the result of the button pushing. A>B will make both VFOs the same - the contents of VFO A are copied into both VFOs. A/B will swap the contents between A and B. While you hold REV, the contents of A and B are swapped only until you release the button. In non-split operation, the A/B button will allow you to rapidly switch between two different transmit (and receive) frequencies. Normal SPLIT operation *might* proceed something like this: Tune to the frequency where you wish to transmit with VFO A (maybe you hear the station that the DX is currently working), then tap A>B. Now tune so you hear the DX station (with VFO A). Press the REV button when you want to listen to your transmit frequency. You can alter your transmit frequency by holding the REV button and tune (with VFO A knob) or by tapping A/B to swap, then re-tune and tap A/B again to swap back. It works fine this way on the K2, but the K3 adds a separate knob for VFO B which will be helpful for refining the transmit frequency, especially when the sub-receiver is installed. With the sub-receiver installed, it becomes more flexible because the sub-receiver will be tuned to your SPLIT transmit frequency and you can listen to that frequency in one ear if you have that selected. There are a thousand other scenarios that are possible for split operation and perhaps others will offer their favorite operating patterns with it. 73, Don W3FPR David Ferrington, M0XDF wrote: > I seem to be very confused about the way VFOa and b control transmit and > want to get some clarification please. > > If you are working split, you transmit on the freq, mode etc., set up in > VFOb - it uses VFOb for transmit. In this scenario, SPLIT, TX and v will be > shown to indicate you are transmitting on VFOb? > > > If you have the 2nd RX (KRX3) fitted and ON (SUB on), VFOb is used to > control it. In other words, the KRX3 module does not have VFO circuits on > it, it requires a VFO (B) to set it up etc. > All the other rules above apply though? > > If the SUB is not on, its pretty much as first described? > Can you even turn on the SUB if its not fitted and if you can, what happens? > > > Finally, the [REV] button described on pg 15 as exchanging VFO a & b > temporarily - what does that mean - while you have it pressed it swaps and > if you release, they go back? If so, while you have it pressed and you Tx, > does if use VFOb settings? > > Thank you Elecraft for making think about what is actually going on inside > my rig - please now help me to think about what is going on inside my head! > Hi > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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Thank you Don, I kinda thought that was how it was and in typing the mail,
came to realise I need to think in terms as you stated. So then I just wanted clarification. I have on more question then - lets say I have the KRX3 (I will when it ships :-). I'm working a split DX, there's one hell of a pile-up (must be 3B7C again). I'm using diversity receive, so I can hear both the DX freq and their QSX, I want to transmit 300 Hz higher than I'm listening to on the Sub - how does one do that quickly? Perhaps use RIT on the SUB, is that possible - i.e., press [B SET] and set RIT to be 300Hxz higher? Then lets assume I don't work them, but want to check if they did listen around where I transmitted, can I then press [REV] and while keeping it depressed, HOLD [CLR] to add the RIT to the SUB freq and clear the RIT? I know these are things I'll be able to figure out once I get the K3, but I got to do something while I'm waiting for the Big Brown Van On 16/10/07 14:18, "Don Wilhelm" <[hidden email]> sent: > David, > > It may help if you mentally divorce the physical VFOs from the A and B > designations and think of the DISPLAYED frequencies. -- Any fool can destroy trees. They cannot defend themselves or run away. And few destroyers of trees ever plant any; nor can planting avail much toward restoring our grand aboriginal giants. It took more than three thousand years to make some of the oldest of the Sequoias, trees that are still standing in perfect strength and beauty, waving and singing in the mighty forests of the Sierra. -John Muir, naturalist, explorer, and writer (1838-1914) _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Don Wilhelm-4
Arrrgggghhh
For RIT below, read XIT Thank you Don, I kinda thought that was how it was and in typing the mail, came to realise I need to think in terms as you stated. So then I just wanted clarification. I have on more question then - lets say I have the KRX3 (I will when it ships :-). I'm working a split DX, there's one hell of a pile-up (must be 3B7C again). I'm using diversity receive, so I can hear both the DX freq and their QSX, I want to transmit 300 Hz higher than I'm listening to on the Sub - how does one do that quickly? Perhaps use RIT on the SUB, is that possible - i.e., press [B SET] and set RIT to be 300Hxz higher? Then lets assume I don't work them, but want to check if they did listen around where I transmitted, can I then press [REV] and while keeping it depressed, HOLD [CLR] to add the RIT to the SUB freq and clear the RIT? I know these are things I'll be able to figure out once I get the K3, but I got to do something while I'm waiting for the Big Brown Van On 16/10/07 14:18, "Don Wilhelm" <[hidden email]> sent: > David, > > It may help if you mentally divorce the physical VFOs from the A and B > designations and think of the DISPLAYED frequencies. -- Any fool can destroy trees. They cannot defend themselves or run away. And few destroyers of trees ever plant any; nor can planting avail much toward restoring our grand aboriginal giants. It took more than three thousand years to make some of the oldest of the Sequoias, trees that are still standing in perfect strength and beauty, waving and singing in the mighty forests of the Sierra. -John Muir, naturalist, explorer, and writer (1838-1914) _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: [K3] clarification on VFO and 2nd Rx - erratum
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David,
I think the real answer to those extensions will have to wait until after the KRX3 ships. I really don't know how RTI and XIT interact with the sub-receiver, nor have I though about how to best utilize it in situations like you have posed. 73, Don W3FPR David Ferrington, M0XDF wrote: > Arrrgggghhh > > For RIT below, read XIT > > > Thank you Don, I kinda thought that was how it was and in typing the mail, > came to realise I need to think in terms as you stated. So then I just > wanted clarification. > > I have on more question then - lets say I have the KRX3 (I will when it > ships :-). I'm working a split DX, there's one hell of a pile-up (must be > 3B7C again). I'm using diversity receive, so I can hear both the DX freq and > their QSX, I want to transmit 300 Hz higher than I'm listening to on the Sub > - how does one do that quickly? > > Perhaps use RIT on the SUB, is that possible - i.e., press [B SET] and set > RIT to be 300Hxz higher? > > Then lets assume I don't work them, but want to check if they did listen > around where I transmitted, can I then press [REV] and while keeping it > depressed, HOLD [CLR] to add the RIT to the SUB freq and clear the RIT? > > I know these are things I'll be able to figure out once I get the K3, but I > got to do something while I'm waiting for the Big Brown Van > > On 16/10/07 14:18, "Don Wilhelm" <[hidden email]> sent: > > >> David, >> >> It may help if you mentally divorce the physical VFOs from the A and B >> designations and think of the DISPLAYED frequencies. >> > > > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Don Wilhelm-4
Don Wilhelm wrote:
> How you alter the frequencies between the VFO A and VFO B is the result > of the button pushing. A>B will make both VFOs the same - the contents > of VFO A are copied into both VFOs. A/B will swap the contents between > A and B. While you hold REV, the contents of A and B are swapped only > until you release the button. > > In non-split operation, the A/B button will allow you to rapidly switch > between two different transmit (and receive) frequencies. When the sub-receiver becomes available, there will also be a special mode which allows you to 'slave' both VFOs to the main tuning knob. This will permit true diversity reception, with separate antennas on each receiver. I am looking forward to trying this, perhaps with a vertical and horizontal antenna. Hopefully one signal will get stronger when the other QSBs! I don't know what Wayne plans for the audio. In the years of AM, diversity setups compared AVC (that's what AGC used to be called) voltages and switched to the best signal. Of course you could listen to the two antennas in separate ears, but it would be interesting to somehow combine the audio signals so you would get a (relatively) QSB-free result. -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: [K3] clarification on VFO and 2nd Rx
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For years here at my place of employment we've offered UHF diversity
receivers where, instead of switching between the two signals, we blend the audio outputs of the receivers in a ratio controlled by the RF level of the received signals in the two receiver sections. Once done using analog circuitry, we do it in the digital domain these days. We refer to it as "ratio combining diversity". Bob NW8L On 10/16/07, Vic K2VCO <[hidden email]> wrote: > > I don't know what Wayne plans for the audio. In the years of AM, > diversity setups compared AVC (that's what AGC used to be called) > voltages and switched to the best signal. Of course you could listen to > the two antennas in separate ears, but it would be interesting to > somehow combine the audio signals so you would get a (relatively) > QSB-free result. > -- > 73, > Vic, K2VCO > Fresno CA > http://www.qsl.net/k2vco Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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