Linear Tuning and Doppler
Ok, let me try this:
I'm not 100% sure what you mean by "tune to the linear birds", but I can guess. Ask again if this answer does not help. A linear satellite has a 20 to 40kHz range in the uplink band where anything it receives is sent to the same (but usually inverted) location in the downlink band. If you want to hear yourself or anyone responding to you, you must tune your receive frequency to match your transmit frequency. It would be nice if such satellites had an exact local oscillator so that you could get the tx and rx frequencies all set ahead of time, but these oscillators do drift. That means you generally have to "tweak" the tuning a bit to get the receive tuned so that you hear yourself clearly. Is that what you are asking?
As to inverting/doppler, yes it does say that in the amateur exam (Extra, I think). I have to say, I thought I understood this, but everytime I started to write about it, I realized "no, that is not right". So for now, I think I'll just say that it does not really matter if you have computer-aided tuning.
73,
Burns WB1FJ
On Mon, Aug 29, 2022 at 12:35 PM Calvin McDonald 7ndel3fr@gmail.com wrote:
I have searched a little and have failed to find the info I'm curious about, so I will ask here.? Can someone point me at a source that will explain why we have to tune to the linear birds and also why inverting transponders work better for Doppler compensation as opposed to non-inverting? Thanks
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Burns,
Just practical/experience sharing.
Actually it does matter using a computer aided tuning if both in a QSO using same e.g. using SatPC32 works very well and may be only slight adjustment of RIT or XIT to keep you in sync through the whole pass of the bird.
Manual tuning also possible and very often used but one need much more skills and mental calculation to keep on a common QRG.
Inverted make it easier for manual operations.
My one cent input.
73
Jean Marc (3B8DU)
On Aug 29, 2022, at 9:10 PM, Burns Fisher wb1fj-bb@fisher.cc wrote:
Ok, let me try this:
I'm not 100% sure what you mean by "tune to the linear birds", but I can guess. Ask again if this answer does not help. A linear satellite has a 20 to 40kHz range in the uplink band where anything it receives is sent to the same (but usually inverted) location in the downlink band. If you want to hear yourself or anyone responding to you, you must tune your receive frequency to match your transmit frequency. It would be nice if such satellites had an exact local oscillator so that you could get the tx and rx frequencies all set ahead of time, but these oscillators do drift. That means you generally have to "tweak" the tuning a bit to get the receive tuned so that you hear yourself clearly. Is that what you are asking?
As to inverting/doppler, yes it does say that in the amateur exam (Extra, I think). I have to say, I thought I understood this, but everytime I started to write about it, I realized "no, that is not right". So for now, I think I'll just say that it does not really matter if you have computer-aided tuning.
73,
Burns WB1FJ
On Mon, Aug 29, 2022 at 12:35 PM Calvin McDonald <7ndel3fr@gmail.com mailto:7ndel3fr@gmail.com> wrote: I have searched a little and have failed to find the info I'm curious about, so I will ask here.? Can someone point me at a source that will explain why we have to tune to the linear birds and also why inverting transponders work better for Doppler compensation as opposed to non-inverting? Thanks
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Thank you Jean Marc. I have had no experience with manual turning, but I guess that is the answer to Calvin's question. Maybe you can say more about why it is easier; I'm not quite seeing it.
On Mon, Aug 29, 2022 at 1:22 PM Jean Marc Momple jean.marc.momple@gmail.com wrote:
Burns,
Just practical/experience sharing.
Actually it does matter using a computer aided tuning if both in a QSO using same e.g. using SatPC32 works very well and may be only slight adjustment of RIT or XIT to keep you in sync through the whole pass of the bird.
Manual tuning also possible and very often used but one need much more skills and mental calculation to keep on a common QRG.
Inverted make it easier for manual operations.
My one cent input.
73
Jean Marc (3B8DU)
On Aug 29, 2022, at 9:10 PM, Burns Fisher wb1fj-bb@fisher.cc wrote:
Ok, let me try this:
I'm not 100% sure what you mean by "tune to the linear birds", but I can guess. Ask again if this answer does not help. A linear satellite has a 20 to 40kHz range in the uplink band where anything it receives is sent to the same (but usually inverted) location in the downlink band. If you want to hear yourself or anyone responding to you, you must tune your receive frequency to match your transmit frequency. It would be nice if such satellites had an exact local oscillator so that you could get the tx and rx frequencies all set ahead of time, but these oscillators do drift. That means you generally have to "tweak" the tuning a bit to get the receive tuned so that you hear yourself clearly. Is that what you are asking?
As to inverting/doppler, yes it does say that in the amateur exam (Extra, I think). I have to say, I thought I understood this, but everytime I started to write about it, I realized "no, that is not right". So for now, I think I'll just say that it does not really matter if you have computer-aided tuning.
73,
Burns WB1FJ
On Mon, Aug 29, 2022 at 12:35 PM Calvin McDonald 7ndel3fr@gmail.com wrote:
I have searched a little and have failed to find the info I'm curious about, so I will ask here.? Can someone point me at a source that will explain why we have to tune to the linear birds and also why inverting transponders work better for Doppler compensation as opposed to non-inverting? Thanks
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HI Calvin, Take a look at this article: https://www.amsat.org/wordpress/wp-content/uploads/2015/02/FDT-WA4SCA.pdf%C2... A must reading to understand Doppler Tuning.
If you plan on doing any manual tuning then use the KE0PBR charts. Rule of thumb use fixed VHF and tune for UHF when adjusting for Doppler. Many rovers including this one uses these charts:https://ke0pbr.wordpress.com/2018/12/31/my-frequency-cheat-sheet/%C2%A0%C2%A... Once you have figured the turning direction it is a easy.
SatPC32 is what most users are using. Another option is http://www.csntechnologies.net/sat%C2%A0 only works on ICOM radios . Both solutions work on full doppler, but you can also use a fix frequency and tune the UHF.
Hope that helps. 73, Adrian AA5UK
On Monday, August 29, 2022 at 12:54:25 PM CDT, Calvin McDonald 7ndel3fr@gmail.com wrote:
Tuning:? Yes, I was referring to the RIT-type tuning required for the transponders.? My question is:? Why are the transponders not designed to hold the frequencies more exact?? I'm guessing it's possible so there must be a design trade-off?? I've recently got into FT4 on the birds and the shift of the frequencies is made very observable by WSJT-X.? The spread is different bird to bird, pass to pass for the same birds and even changes noticeably during a pass with some birds.
Inverting:? I have read several times that transponders typically invert because it makes dealing with Doppler shift easier.? I've laid in bed more than a few hours trying to understand why that would be true - can't figure it out.? That might be because my entire experience with satellites I have used computer controller doppler compensation.
On 8/29/2022 11:25 AM, Burns Fisher wrote:
Thank you Jean Marc.? I have had no experience with manual turning, but I guess that is the answer to Calvin's question.? Maybe you can say more about why it is easier; I'm not quite seeing it. On Mon, Aug 29, 2022 at 1:22 PM Jean Marc Momple jean.marc.momple@gmail.com wrote:
Burns, Just practical/experience sharing.
Actually it does matter using a computer aided tuning if both in a QSO using same e.g. using SatPC32 works very well and may be only slight adjustment of RIT or XIT to keep you in sync through the whole pass of the bird.? Manual tuning also possible and very often used but one need much more skills and mental calculation to keep on a common QRG. Inverted make it easier for manual operations. My one cent input. 73
Jean Marc (3B8DU)
On Aug 29, 2022, at 9:10 PM, Burns Fisher wb1fj-bb@fisher.cc wrote: Ok, let me try this: I'm not 100% sure what you mean by "tune to the linear birds", but I can guess.? Ask again if this answer does not help.? A linear satellite has a 20 to 40kHz range in the uplink band where anything it receives is sent to the same (but usually inverted) location?in the downlink band.? If you want to hear yourself or anyone responding to you, you must tune your receive frequency?to match your transmit frequency.? ?It would be nice if such satellites had an exact local oscillator so that you could get the tx and rx frequencies all set ahead of time, but these oscillators do drift.? That means you generally have to "tweak" the tuning a bit to get the receive tuned so that you hear yourself clearly.? ? Is that what you are asking?
As to inverting/doppler, yes it does say that in the amateur exam (Extra, I think).? I have to say, I thought I understood this, but everytime I started to write about it, I realized "no, that is not right".? So for now, I think I'll just say that it does not really matter if you have computer-aided tuning. 73, Burns WB1FJ On Mon, Aug 29, 2022 at 12:35 PM Calvin McDonald 7ndel3fr@gmail.com wrote:
I have searched a little and have failed to find the info I'm curious about, so I will ask here.? Can someone point me at a source that will explain why we have to tune to the linear birds and also why inverting transponders work better for Doppler compensation as opposed to non-inverting? Thanks
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Omitting the detailed discussion of the Doppler effect, the maximum doppler shift on UHF for our satellites is approximately +/- 10 kHz for a total of 20 kHz. The maximum doppler shift on VHF for our satellites is +/- 3.3 kHz for a total of 6.6 kHz.
When using manual tuning, the recommended procedure is to try to keep the lower frequency (usually VHF) fixed, and tune the higher frequency (usually UHF). For an non-inverting transponder, the maximum shift is the sum of the UHF and VHF shifts, or 20+6.6=26.6 kHz. For inverting transponders, the maximum shift is the *difference* in the UHF and VHF shifts, or 20 minus 6.6 for a total of 13.4 kHz.
So the inverting transponders are “easier” because you don’t have to tune as far across the entire pass, 26.6 kHz vs. 13.4 kHz. “Easier” isn’t “easy”. “Easy” is computer controlled. (Grin)
73, Steve N9IP -- Steve Belter, seb@wintek.commailto:seb@wintek.com
From: Calvin McDonald 7ndel3fr@gmail.com Reply-To: "ck1@ckmcdonald.com" ck1@ckmcdonald.com Date: Monday, August 29, 2022 at 1:54 PM To: AMSAT-BB amsat-bb@amsat.org Cc: "ck1@ckmcdonald.com" ck1@ckmcdonald.com Subject: [AMSAT-BB] Re: Linear Tuning and Doppler
Tuning:? Yes, I was referring to the RIT-type tuning required for the transponders.? My question is:? Why are the transponders not designed to hold the frequencies more exact?? I'm guessing it's possible so there must be a design trade-off?? I've recently got into FT4 on the birds and the shift of the frequencies is made very observable by WSJT-X.? The spread is different bird to bird, pass to pass for the same birds and even changes noticeably during a pass with some birds.
Inverting:? I have read several times that transponders typically invert because it makes dealing with Doppler shift easier.? I've laid in bed more than a few hours trying to understand why that would be true - can't figure it out.? That might be because my entire experience with satellites I have used computer controller doppler compensation.
On 8/29/2022 11:25 AM, Burns Fisher wrote: Thank you Jean Marc.? I have had no experience with manual turning, but I guess that is the answer to Calvin's question.? Maybe you can say more about why it is easier; I'm not quite seeing it.
On Mon, Aug 29, 2022 at 1:22 PM Jean Marc Momple <jean.marc.momple@gmail.commailto:jean.marc.momple@gmail.com> wrote: Burns,
Just practical/experience sharing.
Actually it does matter using a computer aided tuning if both in a QSO using same e.g. using SatPC32 works very well and may be only slight adjustment of RIT or XIT to keep you in sync through the whole pass of the bird.?
Manual tuning also possible and very often used but one need much more skills and mental calculation to keep on a common QRG.
Inverted make it easier for manual operations.
My one cent input.
73
Jean Marc (3B8DU)
On Aug 29, 2022, at 9:10 PM, Burns Fisher <wb1fj-bb@fisher.ccmailto:wb1fj-bb@fisher.cc> wrote:
Ok, let me try this:
I'm not 100% sure what you mean by "tune to the linear birds", but I can guess.? Ask again if this answer does not help.? A linear satellite has a 20 to 40kHz range in the uplink band where anything it receives is sent to the same (but usually inverted) location?in the downlink band.? If you want to hear yourself or anyone responding to you, you must tune your receive frequency?to match your transmit frequency.? ?It would be nice if such satellites had an exact local oscillator so that you could get the tx and rx frequencies all set ahead of time, but these oscillators do drift.? That means you generally have to "tweak" the tuning a bit to get the receive tuned so that you hear yourself clearly.? ? Is that what you are asking?
As to inverting/doppler, yes it does say that in the amateur exam (Extra, I think).? I have to say, I thought I understood this, but everytime I started to write about it, I realized "no, that is not right".? So for now, I think I'll just say that it does not really matter if you have computer-aided tuning.
73,
Burns WB1FJ
On Mon, Aug 29, 2022 at 12:35 PM Calvin McDonald <7ndel3fr@gmail.commailto:7ndel3fr@gmail.com> wrote: I have searched a little and have failed to find the info I'm curious about, so I will ask here.? Can someone point me at a source that will explain why we have to tune to the linear birds and also why inverting transponders work better for Doppler compensation as opposed to non-inverting? Thanks
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Stephen E. Belter said (in part):
So the inverting transponders are “easier” because you don’t have to tune as far across the entire pass, 26.6 kHz vs. 13.4 kHz. “Easier” isn’t “easy”. “Easy” is computer controlled. (Grin)
With a little practice, it's not all that hard. I never used any form of computer control of the radio and made thousands of SSB contacts on linear satellites. And yes, the inverting transponders are easier as Stephen explained.
73 ----- Jim Walls - K6CCC jim@k6ccc.org
It’s too bad LilacSat-2’s linear transponder mode was only activated a couple of times. It was capable of being configured as a non-inverting V/u linear transponder. Coupled with the 500 km orbit, manual tuning was real fun and it served as a great demonstration of why we use inverting linear transponders on VHF/UHF LEOs.
73,
Paul, N8HM
On Mon, Aug 29, 2022 at 14:17 Stephen E. Belter seb@wintek.com wrote:
Omitting the detailed discussion of the Doppler effect, the maximum doppler shift on UHF for our satellites is approximately +/- 10 kHz for a total of 20 kHz. The maximum doppler shift on VHF for our satellites is +/- 3.3 kHz for a total of 6.6 kHz.
When using manual tuning, the recommended procedure is to try to keep the lower frequency (usually VHF) fixed, and tune the higher frequency (usually UHF). For an non-inverting transponder, the maximum shift is the sum of the UHF and VHF shifts, or 20+6.6=26.6 kHz. For inverting transponders, the maximum shift is the **difference** in the UHF and VHF shifts, or 20 minus 6.6 for a total of 13.4 kHz.
So the inverting transponders are “easier” because you don’t have to tune as far across the entire pass, 26.6 kHz vs. 13.4 kHz. “Easier” isn’t “easy”. “Easy” is computer controlled. (Grin)
73, Steve N9IP
--
Steve Belter, seb@wintek.com
*From: *Calvin McDonald 7ndel3fr@gmail.com *Reply-To: *"ck1@ckmcdonald.com" ck1@ckmcdonald.com *Date: *Monday, August 29, 2022 at 1:54 PM *To: *AMSAT-BB amsat-bb@amsat.org *Cc: *"ck1@ckmcdonald.com" ck1@ckmcdonald.com *Subject: *[AMSAT-BB] Re: Linear Tuning and Doppler
Tuning:? Yes, I was referring to the RIT-type tuning required for the transponders.? My question is:? Why are the transponders not designed to hold the frequencies more exact?? I'm guessing it's possible so there must be a design trade-off?? I've recently got into FT4 on the birds and the shift of the frequencies is made very observable by WSJT-X.? The spread is different bird to bird, pass to pass for the same birds and even changes noticeably during a pass with some birds.
Inverting:? I have read several times that transponders typically invert because it makes dealing with Doppler shift easier.? I've laid in bed more than a few hours trying to understand why that would be true - can't figure it out.? That might be because my entire experience with satellites I have used computer controller doppler compensation.
On 8/29/2022 11:25 AM, Burns Fisher wrote:
Thank you Jean Marc.? I have had no experience with manual turning, but I guess that is the answer to Calvin's question.? Maybe you can say more about why it is easier; I'm not quite seeing it.
On Mon, Aug 29, 2022 at 1:22 PM Jean Marc Momple < jean.marc.momple@gmail.com> wrote:
Burns,
Just practical/experience sharing.
Actually it does matter using a computer aided tuning if both in a QSO using same e.g. using SatPC32 works very well and may be only slight adjustment of RIT or XIT to keep you in sync through the whole pass of the bird.?
Manual tuning also possible and very often used but one need much more skills and mental calculation to keep on a common QRG.
Inverted make it easier for manual operations.
My one cent input.
73
Jean Marc (3B8DU)
On Aug 29, 2022, at 9:10 PM, Burns Fisher wb1fj-bb@fisher.cc wrote:
Ok, let me try this:
I'm not 100% sure what you mean by "tune to the linear birds", but I can guess.? Ask again if this answer does not help.? A linear satellite has a 20 to 40kHz range in the uplink band where anything it receives is sent to the same (but usually inverted) location?in the downlink band.? If you want to hear yourself or anyone responding to you, you must tune your receive frequency?to match your transmit frequency.? ?It would be nice if such satellites had an exact local oscillator so that you could get the tx and rx frequencies all set ahead of time, but these oscillators do drift.? That means you generally have to "tweak" the tuning a bit to get the receive tuned so that you hear yourself clearly.? ? Is that what you are asking?
As to inverting/doppler, yes it does say that in the amateur exam (Extra, I think).? I have to say, I thought I understood this, but everytime I started to write about it, I realized "no, that is not right".? So for now, I think I'll just say that it does not really matter if you have computer-aided tuning.
73,
Burns WB1FJ
On Mon, Aug 29, 2022 at 12:35 PM Calvin McDonald 7ndel3fr@gmail.com wrote:
I have searched a little and have failed to find the info I'm curious about, so I will ask here.? Can someone point me at a source that will explain why we have to tune to the linear birds and also why inverting transponders work better for Doppler compensation as opposed to non-inverting? Thanks
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Does anyone have first hand experience with an Icom CIV to USB cable that is compatible with WIN11? If so the make, model, and source please...
Thanks...
73 Jeff kb2m
i ordered this one for use with a 9700. However, I am using it with a Mac, so no guarantees on Windows, although it claims to work.
https://smile.amazon.com/gp/product/B08HLLSHTN
On Sun, Sep 4, 2022 at 7:42 PM jeff griffin kb2mjeff@att.net wrote:
Does anyone have first hand experience with an Icom CIV to USB cable that is compatible with WIN11? If so the make, model, and source please...
Thanks...
73 Jeff kb2m
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Hi Jeff,
I home-brewed low cost USB CI-V cable for my recent AT3VLH Lighthouse Activation, it worked very well for me and I did hundreds of qso on Digital.
I built a simple CIV cable with easily available USB to TTL converter. I choosen FTDI chip based converter which are very reliable and it's plug & play type device (no drivers needed in latest Windows). Though I used mine with Win10 but guess it will work pretty well with Win-11 too.
Here is construction link I followed:
https://owenduffy.net/blog/?p=6756
Hope this could a good option for you or any interested ham who opt for little brewing.
Thank you, 73 Rajesh Vagadia VU2EXP
On Mon 5 Sep, 2022, 5:12 AM jeff griffin, kb2mjeff@att.net wrote:
Does anyone have first hand experience with an Icom CIV to USB cable that is compatible with WIN11? If so the make, model, and source please...
Thanks...
73 Jeff kb2m
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I haven't been following this thread closely, so ignore if out of place. There are 2 connections on the IC-9700 that can be quite confusing and when you throw in the 2 USB ports it can be very. The Data Jack labeled as 5 in the instruction manual. This is a 2.5 mm TRS plug. i use this to get NMEA data from a GPS receiver. I built my own cable for a unit that uses a DB-9 connection. The CIV/Remote which is labeled as 8 in the instruction manual. This is a 3.5 mm TS plug. It can be used if you want to use the waterfall function in SatPC32. I use it for SatPC32 to control the radio when doing digital modes and Keyboard CW. this the link https://www.amazon.com/gp/product/B004L0T4UM/ref=ppx_yo_dt_b_search_asin_tit... Cheers,Jerry N5EKO
On Monday, September 5, 2022 at 10:37:54 AM CDT, Rajesh Vagadia - VU2EXP vu2exp@gmail.com wrote:
Hi Jeff, I home-brewed low cost USB CI-V cable for my recent AT3VLH Lighthouse Activation, it worked very well for me and I did hundreds of qso on Digital. I built a simple CIV cable with easily available USB to TTL converter. I choosen FTDI chip based converter which are very reliable and it's plug & play type device (no drivers needed in latest Windows). Though I used mine with Win10 but guess it will work pretty well with Win-11 too. Here is construction link I followed: https://owenduffy.net/blog/?p=6756 Hope this could a good option for you or any interested ham who opt for little brewing. Thank you, 73Rajesh Vagadia VU2EXP
On Mon 5 Sep, 2022, 5:12 AM jeff griffin, kb2mjeff@att.net wrote:
Does anyone have first hand experience with an Icom CIV to USB cable that is compatible with WIN11? If so the make, model, and source please...
Thanks...
73 Jeff kb2m
-----------------------------------------------------------
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Received thebestkong CI-V CT-17 Cat Cable for ICOM USB to TTL cable from Amazon that was supposed to work according to several Amazon users. Here is the error I get when I try to install...
I know I can maybe search the internet for some driver that will work, but when WIN11 updates the associated drivers I will be doing it again. I also don't have the desire to build a USB to TTL from scratch, I did this when this was viable 30 years ago when Icom CIV box was expensive and I could build my own cable with a 1 transistor design that would fit into a DB9 shell for a few dollars. So I am still looking for an off the shelf USB to TTL CIV cable from Amazon or eBay that will work with WIN11 supplied drivers.
But wait I have one, a 10 year old USB to TTL Elecraft cable that came with my KPA500 Amplifier for computer control.
So once again does anyone have a part number for a cable that that they have working with WIN11? I would like to return the cable I'm now temporally using with my 9700 back to my Elecraft Amp where it belongs :-)
73 Jeff kb2m
9/4/2022 7:41 PM, jeff griffin wrote:
Does anyone have first hand experience with an Icom CIV to USB cable that is compatible with WIN11? If so the make, model, and source please...
Thanks...
73 Jeff kb2m
Does Elecraft sell the cable separately?
73,
Alan WA4SCA
On Fri, Sep 9, 2022, 5:38 PM jeff griffin kb2mjeff@att.net wrote:
Received the bestkong CI-V CT-17 Cat Cable for ICOM USB to TTL cable from Amazon that was supposed to work according to several Amazon users. Here is the error I get when I try to install...
I know I can maybe search the internet for some driver that will work, but when WIN11 updates the associated drivers I will be doing it again. I also don't have the desire to build a USB to TTL from scratch, I did this when this was viable 30 years ago when Icom CIV box was expensive and I could build my own cable with a 1 transistor design that would fit into a DB9 shell for a few dollars. So I am still looking for an off the shelf USB to TTL CIV cable from Amazon or eBay that will work with WIN11 supplied drivers.
But wait I have one, a 10 year old USB to TTL Elecraft cable that came with my KPA500 Amplifier for computer control.
So once again does anyone have a part number for a cable that that they have working with WIN11? I would like to return the cable I'm now temporally using with my 9700 back to my Elecraft Amp where it belongs :-)
73 Jeff kb2m
9/4/2022 7:41 PM, jeff griffin wrote:
Does anyone have first hand experience with an Icom CIV to USB cable that is compatible with WIN11? If so the make, model, and source please...
Thanks...
73 Jeff kb2m
Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
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This is what I use.
https://www.blackcatsystems.com/usbciv/usb_icom_ci-v_interface.html
On Sep 9, 2022, at 6:51 PM, Alan Biddle wa4sca@gmail.com wrote:
Does Elecraft sell the cable separately?
73,
Alan WA4SCA
On Fri, Sep 9, 2022, 5:38 PM jeff griffin kb2mjeff@att.net wrote: Received the bestkong CI-V CT-17 Cat Cable for ICOM USB to TTL cable from Amazon that was supposed to work according to several Amazon users. Here is the error I get when I try to install...
I know I can maybe search the internet for some driver that will work, but when WIN11 updates the associated drivers I will be doing it again. I also don't have the desire to build a USB to TTL from scratch, I did this when this was viable 30 years ago when Icom CIV box was expensive and I could build my own cable with a 1 transistor design that would fit into a DB9 shell for a few dollars. So I am still looking for an off the shelf USB to TTL CIV cable from Amazon or eBay that will work with WIN11 supplied drivers.
But wait I have one, a 10 year old USB to TTL Elecraft cable that came with my KPA500 Amplifier for computer control.
So once again does anyone have a part number for a cable that that they have working with WIN11? I would like to return the cable I'm now temporally using with my 9700 back to my Elecraft Amp where it belongs :-)
73 Jeff kb2m
9/4/2022 7:41 PM, jeff griffin wrote:
Does anyone have first hand experience with an Icom CIV to USB cable that is compatible with WIN11? If so the make, model, and source please...
Thanks...
73 Jeff kb2m
Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
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Tom, looking at the info about the cable on the link you supplied I see it uses an FTDI chip. I will try a simple cable off of Amazon that specifies that chip. I will report back here....
73 Jeff kb2m
On 9/9/2022 7:36 PM, Tom Cain wrote:
This is what I use.
https://www.blackcatsystems.com/usbciv/usb_icom_ci-v_interface.html
On Sep 9, 2022, at 6:51 PM, Alan Biddle wa4sca@gmail.com wrote:
Does Elecraft sell the cable separately?
73,
Alan WA4SCA
On Fri, Sep 9, 2022, 5:38 PM jeff griffin kb2mjeff@att.net wrote:
Received thebestkong CI-V CT-17 Cat Cable for ICOM USB to TTL cable from Amazon that was supposed to work according to several Amazon users. Here is the error I get when I try to install... I know I can maybe search the internet for some driver that will work, but when WIN11 updates the associated drivers I will be doing it again. I also don't have the desire to build a USB to TTL from scratch, I did this when this was viable 30 years ago when Icom CIV box was expensive and I could build my own cable with a 1 transistor design that would fit into a DB9 shell for a few dollars. So I am still looking for an off the shelf USB to TTL CIV cable from Amazon or eBay that will work with WIN11 supplied drivers. But wait I have one, a 10 year old USB to TTL Elecraft cable that came with my KPA500 Amplifier for computer control. So once again does anyone have a part number for a cable that that they have working with WIN11? I would like to return the cable I'm now temporally using with my 9700 back to my Elecraft Amp where it belongs :-) 73 Jeff kb2m 9/4/2022 7:41 PM, jeff griffin wrote:Does anyone have first hand experience with an Icom CIV to USB cable that is compatible with WIN11? If so the make, model, and source please... Thanks... 73 Jeff kb2m----------------------------------------------------------- Sent via AMSAT-BB(a)amsat.org <http://amsat.org>. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/ View archives of this mailing list at https://mailman.amsat.org/hyperkitty/list/amsat-bb@amsat.org To unsubscribe send an email to amsat-bb-leave(a)amsat.org <http://amsat.org> Manage all of your AMSAT-NA mailing list preferences at https://mailman.amsat.orgdKkCjWH5mKj9y1HS.png
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Try a Gearmo FTDI cable. Gearmo site says they support win11
Floyd KC5QBC
On Sep 9, 2022, at 7:38 PM, jeff griffin kb2mjeff@att.net wrote:
Tom, looking at the info about the cable on the link you supplied I see it uses an FTDI chip. I will try a simple cable off of Amazon that specifies that chip. I will report back here....
73 Jeff kb2m
On 9/9/2022 7:36 PM, Tom Cain wrote: This is what I use.
https://www.blackcatsystems.com/usbciv/usb_icom_ci-v_interface.html
On Sep 9, 2022, at 6:51 PM, Alan Biddle wa4sca@gmail.com wrote:
Does Elecraft sell the cable separately?
73,
Alan WA4SCA
On Fri, Sep 9, 2022, 5:38 PM jeff griffin kb2mjeff@att.net wrote: Received the bestkong CI-V CT-17 Cat Cable for ICOM USB to TTL cable from Amazon that was supposed to work according to several Amazon users. Here is the error I get when I try to install...
I know I can maybe search the internet for some driver that will work, but when WIN11 updates the associated drivers I will be doing it again. I also don't have the desire to build a USB to TTL from scratch, I did this when this was viable 30 years ago when Icom CIV box was expensive and I could build my own cable with a 1 transistor design that would fit into a DB9 shell for a few dollars. So I am still looking for an off the shelf USB to TTL CIV cable from Amazon or eBay that will work with WIN11 supplied drivers.
But wait I have one, a 10 year old USB to TTL Elecraft cable that came with my KPA500 Amplifier for computer control.
So once again does anyone have a part number for a cable that that they have working with WIN11? I would like to return the cable I'm now temporally using with my 9700 back to my Elecraft Amp where it belongs :-)
73 Jeff kb2m
9/4/2022 7:41 PM, jeff griffin wrote:
Does anyone have first hand experience with an Icom CIV to USB cable that is compatible with WIN11? If so the make, model, and source please...
Thanks...
73 Jeff kb2m
Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
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<dKkCjWH5mKj9y1HS.png>
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Hi Alan, no I don't see it listed on Elecraft's website anymore. What's odd about this is I can't believe someone on here hasn't bought a comparable simple inline cable that would work with WIN11 and an Icom radio. So I went through the Bestkong cable, I will keep trying different and returning cables till I get a winner then I will post here....
73 Jeff kb2m
On 9/9/2022 6:49 PM, Alan Biddle wrote:
Does Elecraft sell the cable separately?
73,
Alan WA4SCA
On Fri, Sep 9, 2022, 5:38 PM jeff griffin kb2mjeff@att.net wrote:
Received thebestkong CI-V CT-17 Cat Cable for ICOM USB to TTL cable from Amazon that was supposed to work according to several Amazon users. Here is the error I get when I try to install... I know I can maybe search the internet for some driver that will work, but when WIN11 updates the associated drivers I will be doing it again. I also don't have the desire to build a USB to TTL from scratch, I did this when this was viable 30 years ago when Icom CIV box was expensive and I could build my own cable with a 1 transistor design that would fit into a DB9 shell for a few dollars. So I am still looking for an off the shelf USB to TTL CIV cable from Amazon or eBay that will work with WIN11 supplied drivers. But wait I have one, a 10 year old USB to TTL Elecraft cable that came with my KPA500 Amplifier for computer control. So once again does anyone have a part number for a cable that that they have working with WIN11? I would like to return the cable I'm now temporally using with my 9700 back to my Elecraft Amp where it belongs :-) 73 Jeff kb2m 9/4/2022 7:41 PM, jeff griffin wrote:Does anyone have first hand experience with an Icom CIV to USB cable that is compatible with WIN11? If so the make, model, and source please... Thanks... 73 Jeff kb2m----------------------------------------------------------- Sent via AMSAT-BB(a)amsat.org <http://amsat.org>. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/ View archives of this mailing list at https://mailman.amsat.org/hyperkitty/list/amsat-bb@amsat.org To unsubscribe send an email to amsat-bb-leave(a)amsat.org <http://amsat.org> Manage all of your AMSAT-NA mailing list preferences at https://mailman.amsat.org
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Buy an FTDI USB/serial converter and build the cable yourself.
On 09/09/2022 18:36 EDT jeff griffin kb2mjeff@att.net wrote:
Received thebestkong CI-V CT-17 Cat Cable for ICOM USB to TTL cable from Amazon that was supposed to work according to several Amazon users. Here is the error I get when I try to install...
I know I can maybe search the internet for some driver that will work, but when WIN11 updates the associated drivers I will be doing it again. I also don't have the desire to build a USB to TTL from scratch, I did this when this was viable 30 years ago when Icom CIV box was expensive and I could build my own cable with a 1 transistor design that would fit into a DB9 shell for a few dollars. So I am still looking for an off the shelf USB to TTL CIV cable from Amazon or eBay that will work with WIN11 supplied drivers.
But wait I have one, a 10 year old USB to TTL Elecraft cable that came with my KPA500 Amplifier for computer control.
So once again does anyone have a part number for a cable that that they have working with WIN11? I would like to return the cable I'm now temporally using with my 9700 back to my Elecraft Amp where it belongs :-)
73 Jeff kb2m
9/4/2022 7:41 PM, jeff griffin wrote:
Does anyone have first hand experience with an Icom CIV to USB cable that is compatible with WIN11? If so the make, model, and source please...
Thanks...
73 Jeff kb2m
----------------------------------------------------------- Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/ View archives of this mailing list at https://mailman.amsat.org/hyperkitty/list/amsat-bb@amsat.org To unsubscribe send an email to amsat-bb-leave(a)amsat.org Manage all of your AMSAT-NA mailing list preferences at https://mailman.amsat.org
Nigel A. Gunn, ///shoulders.outwards.resolutions tel +1-937-971-0366 Amateur Radio G8IFF W8IFF and GMRS WRBV701, e-mail nigel@ngunn.net www http://www.ngunn.net
On 8/29/22 12:53, Calvin McDonald wrote:
Why are the transponders not designed to hold the frequencies more exact??
Because it doesn't know how fast you are traveling, relative to its position in space. That also applies for everyone else listening to it. :-)
https://en.wikipedia.org/wiki/Doppler_effect
(eg. it will be exactly on frequency directly above you, but way off for someone else looking at it near the horizon)
--- Zach N0ZGO
Zach, I think he was really asking why are the rx and tx not consistently distant from each other. Part of the answer is doppler (UHF has more shift than VHF) but I think the annoying thing that we just have to deal with is that each time most linears come by you have to tweak the rx or tx to match even if you have exact keps, CAT, etc. And I think the answer to that is just COTS parts in a really difficult environment. Agree?
73,
Burns WB1FJ
On Mon, Aug 29, 2022 at 3:40 PM Zach Metzinger zmetzing@pobox.com wrote:
On 8/29/22 12:53, Calvin McDonald wrote:
Why are the transponders not designed to hold the frequencies more
exact??
Because it doesn't know how fast you are traveling, relative to its position in space. That also applies for everyone else listening to it. :-)
Unlike a cosy shack, the temperature of a satellite can change dramatically during the orbit. +30 degrees down to -20 degrees C is not unusual for a 1U cubesat and you will get drift as a result.As the satellite size increases and you have more solar cells, (and thermal mass) you may be able to devote more power to keeping the frequencies stable....It's all a trade off which sometimes works but sometimes does not. 73 David G0MRF
To: amsat-bb@amsat.org Sent: Mon, 29 Aug 2022 19:39 Subject: [AMSAT-BB] Re: Linear Tuning and Doppler
On 8/29/22 12:53, Calvin McDonald wrote:
Why are the transponders not designed to hold the frequencies more exact??
-----------------------------------------------------------
participants (16)
-
Adrian Engele -
Alan Biddle -
Burns Fisher -
Calvin McDonald -
David G0MRF -
Floyd Rodgers -
Jean Marc Momple -
jeff griffin -
Jerry Davis -
jim＠k6ccc.org -
Nigel A. Gunn G8IFF/W8IFF -
Paul Stoetzer -
Rajesh Vagadia - VU2EXP -
Stephen E. Belter -
Tom Cain -
Zach Metzinger