... Yaesu FT-8800 ...
Really? Dual-receive, indeed. And will perform crossband repeating. But I can transmit on one band and simultaneously hear myself on another with a FT-8800?
Really? Dual-receive, indeed. And will perform crossband repeating. But I can transmit on one band and simultaneously hear myself on another with a FT-8800?
How else would it be able to cross band repeat? Page three of the manual:
"Featuring 1054 memory channels (527 channels each for "Main" and "Sub" band), full duplex operation with independent Volume and Squelch controls, and built-in CTCSS and DCS encoder/decoder circuits, ..."
73, Drew KO4MA
My FT-8800 is my main FM sat rig. It is the perfect 'mobile' type for FM sats with the independent volume, squelch and tuning controls for each side (band). Full duplex crossband works perfectly. I even have mine rigged up with an external speaker/switch box with headphone jack. I can plug in the headphones, switch off the speaker and talk full duplex without feedback.
Having the 6 pre-program buttons on the front helps too. Mine is set up so that when I press button six, the VHF side goes to the AO-51 uplink and the UHF side goes to the downlink. I tune the UHF side as the doppler changes. Button 5 switches to AO-27 and SO-50.
Ernie W8EH
Andrew Glasbrenner wrote:
Really? Dual-receive, indeed. And will perform crossband repeating. But I can transmit on one band and simultaneously hear myself on another with a FT-8800?
How else would it be able to cross band repeat? Page three of the manual:
"Featuring 1054 memory channels (527 channels each for "Main" and "Sub" band), full duplex operation with independent Volume and Squelch controls, and built-in CTCSS and DCS encoder/decoder circuits, ..."
73, Drew KO4MA
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Really? Dual-receive, indeed. And will perform crossband repeating. But I can transmit on one band and simultaneously hear myself on another with a FT-8800?
Yes, the FT-8800 will let you transmit on one band while receiving on another. Having separate volume and tuning knobs for each VFO, something that similar radios from the other manufacturers lack, make it nice for FM satellite work. I had one earlier this year, before leaving it in Mexico as part of a complete FM satellite station (one I might use on a future trip, if I didn't haul my own gear).
If I had to replace my IC-2720H, I would probably get an FT-8800 as the replacement. Price is good, better than the IC-2820H which was Icom's replacement for the IC-2720H, and the separate knobs for each VFO made it a better (for me) choice than the current Kenwood 2m/70cm FM mobiles (TM-D710 or TM-V71A). And, as Drew mentioned, its ability to function as a cross-band repeater ensures it can work with the satellites in cross-band full-duplex mode.
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/
On Mon, 1 Jun 2009 13:23:44 -0700, "Patrick STODDARD (WD9EWK/VA7EWK)" amsat-bb@wd9ewk.net said:
If I had to replace my IC-2720H, I would probably get an FT-8800 as the replacement. Price is good, better than the IC-2820H which was Icom's replacement for the IC-2720H, and the separate knobs for each VFO made it a better (for me) choice than the current Kenwood 2m/70cm FM mobiles (TM-D710 or TM-V71A). And, as Drew mentioned, its ability to function as a cross-band repeater ensures it can work with the satellites in cross-band full-duplex mode.
I would say "get the 2820 and try out some D-STAR/digital stuff too". Plus the 2820 has the GPS in it... with the D-STAR installed...
IC-2820 and Kenwood's TNC/control head thing together makes a pretty cool little "digital geek" mobile station, and with the 2820 also capable of duplex operation...
Lots of toys = fun. Of course, to get the full utilization out of the D-STAR portion, you really need to be in the coverage of a Gateway (internet) equipped D-STAR repeater...
Stuff to think about...
Nate WY0X -- Nate Duehr nate@natetech.com
{queue thunder clap}
Wait a minute... How can a radio be capable of cross-band repeat and not be full duplex? I believe the answer is no. Cross-band (analog) repeating is inherently full duplex. So, perhaps this is a simple way to ask a non-satellite person, without having to explain what duplex means.
By the way, my Alinco DR-610 mobile rig is also full-duplex. You may add it to the list. (In fact, it's got some down-right-weird modes, between the two sides of the radio, that it's sometimes anyone's guess what will happen when you key up.)
Greg KO6TH
From: clintbrad4d@earthlink.net To: amsat-bb@amsat.org Date: Mon, 1 Jun 2009 12:37:16 -0700 Subject: [amsat-bb] Re: true duplex radios
... Yaesu FT-8800 ...
Really? Dual-receive, indeed. And will perform crossband repeating. But I can transmit on one band and simultaneously hear myself on another with a FT-8800? _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_________________________________________________________________ Lauren found her dream laptop. Find the PC that’s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290
Hi All,
In my experience, you dont have to listen to the output channal of a repeater, while transmitting to its input, ie you dont have to hear your own signals coming back through the repeater. BUT you do (ideally) when working through a satellite.
Again im my experience, such a radio as Greg has described is called a "half duplex" one.
The big advantage of using a full duplex radio for satellites is that you can check if you are being rebroadcast by the satellite or not, without relying on others to tell you. (You can also change the polority of the up link signal, for maximium smoke!)
73 Jim G3WGM
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org]On Behalf Of Greg D. Sent: 02 June 2009 07:12 To: clintbrad4d@earthlink.net; amsat-bb@amsat.org Subject: [amsat-bb] Re: true duplex radios
{queue thunder clap}
Wait a minute... How can a radio be capable of cross-band repeat and not be full duplex? I believe the answer is no. Cross-band (analog) repeating is inherently full duplex. So, perhaps this is a simple way to ask a non-satellite person, without having to explain what duplex means.
By the way, my Alinco DR-610 mobile rig is also full-duplex. You may add it to the list. (In fact, it's got some down-right-weird modes, between the two sides of the radio, that it's sometimes anyone's guess what will happen when you key up.)
Greg KO6TH
From: clintbrad4d@earthlink.net To: amsat-bb@amsat.org Date: Mon, 1 Jun 2009 12:37:16 -0700 Subject: [amsat-bb] Re: true duplex radios
... Yaesu FT-8800 ...
Really? Dual-receive, indeed. And will perform crossband repeating. But I can transmit on one band and simultaneously hear myself on another with a FT-8800? _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Lauren found her dream laptop. Find the PC that’s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.339 / Virus Database: 270.12.48/2147 - Release Date: 05/31/09 20:45:00
No. Half Duplex is when you can both receive and transmit but not simultaneously. Full Duplex is when tou can both receive and transmit simultaneously Simples is when you can either receive or transmit but not both.
Jim Heck wrote:
Again im my experience, such a radio as Greg has described is called a "half duplex" one.
Hi Jim and others.
For ordinary Repeaters the Rx/Tx in the same band is mandatory. But just think of the filtering needed for TX'ing lots og watts just 600kHz away from your Rx-frq. This is also the reason why most repeaters (at least that I know of) uses really big cavity-filters.
But for Rx/Tx on the same frequency - Forget it. What would be the purpose anyway?
In my terms, a full-duplex radio is a radio that listens on one band, whilst transmitting on another.
Regards OZ1TMM, Martin
Jim Heck wrote:
Hi All,
In my experience, you dont have to listen to the output channal of a repeater, while transmitting to its input, ie you dont have to hear your own signals coming back through the repeater. BUT you do (ideally) when working through a satellite.
Again im my experience, such a radio as Greg has described is called a "half duplex" one.
The big advantage of using a full duplex radio for satellites is that you can check if you are being rebroadcast by the satellite or not, without relying on others to tell you. (You can also change the polority of the up link signal, for maximium smoke!)
73 Jim G3WGM
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org]On Behalf Of Greg D. Sent: 02 June 2009 07:12 To: clintbrad4d@earthlink.net; amsat-bb@amsat.org Subject: [amsat-bb] Re: true duplex radios
{queue thunder clap}
Wait a minute... How can a radio be capable of cross-band repeat and not be full duplex? I believe the answer is no. Cross-band (analog) repeating is inherently full duplex. So, perhaps this is a simple way to ask a non-satellite person, without having to explain what duplex means.
By the way, my Alinco DR-610 mobile rig is also full-duplex. You may add it to the list. (In fact, it's got some down-right-weird modes, between the two sides of the radio, that it's sometimes anyone's guess what will happen when you key up.)
Greg KO6TH
From: clintbrad4d@earthlink.net To: amsat-bb@amsat.org Date: Mon, 1 Jun 2009 12:37:16 -0700 Subject: [amsat-bb] Re: true duplex radios
... Yaesu FT-8800 ...
Really? Dual-receive, indeed. And will perform crossband repeating. But I can transmit on one band and simultaneously hear myself on another with a FT-8800? _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Lauren found her dream laptop. Find the PC that’s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.339 / Virus Database: 270.12.48/2147 - Release Date: 05/31/09 20:45:00
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Hi Martin and other AMSAT'ers, This is a bit beside the subject but I seemed to recall that OSCAR-III was running full duplex in the 2 metre band:
http://www.amsat.org/amsat-new/satellites/satInfo.php?satID=26&retURL=sa...
That is not on the same frequency - but the same band.
If you look at some systems like the Marisat system or some of the scientific satellites in the 2 GHz band it is the same.
To return to the subject I hope someone will gather all the information about full duplex transceivers that have been on the amsat-bb during the last days.
73 OZ1MY Ib ----- Original Message ----- From: "Martin" tmm@trutter.dk Cc: AMSAT-bb@amsat.org Sent: Tuesday, June 02, 2009 9:02 PM Subject: [amsat-bb] Re: true duplex radios
Hi Jim and others.
For ordinary Repeaters the Rx/Tx in the same band is mandatory. But just think of the filtering needed for TX'ing lots og watts just 600kHz away from your Rx-frq. This is also the reason why most repeaters (at least that I know of) uses really big cavity-filters.
But for Rx/Tx on the same frequency - Forget it. What would be the purpose anyway?
In my terms, a full-duplex radio is a radio that listens on one band, whilst transmitting on another.
Regards OZ1TMM, Martin
Jim Heck wrote:
Hi All,
In my experience, you dont have to listen to the output channal of a
repeater,
while transmitting to its input, ie you dont have to hear your own signals
coming
back through the repeater. BUT you do (ideally) when working through a
satellite.
Again im my experience, such a radio as Greg has described is called a
"half
duplex" one.
The big advantage of using a full duplex radio for satellites is that
you can
check if you are being rebroadcast by the satellite or not, without
relying on
others to tell you. (You can also change the polority of the up link
signal, for
maximium smoke!)
73 Jim G3WGM
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org]On Behalf Of Greg D. Sent: 02 June 2009 07:12 To: clintbrad4d@earthlink.net; amsat-bb@amsat.org Subject: [amsat-bb] Re: true duplex radios
{queue thunder clap}
Wait a minute... How can a radio be capable of cross-band repeat and not be full duplex? I believe the answer is no. Cross-band (analog) repeating is inherently full duplex. So, perhaps this is a simple way to ask a non-satellite person, without having to explain what duplex means.
By the way, my Alinco DR-610 mobile rig is also full-duplex. You may add it to the list. (In fact, it's got some down-right-weird modes, between the two sides of the radio, that it's sometimes anyone's guess what will happen when you key up.)
Greg KO6TH
From: clintbrad4d@earthlink.net To: amsat-bb@amsat.org Date: Mon, 1 Jun 2009 12:37:16 -0700 Subject: [amsat-bb] Re: true duplex radios
... Yaesu FT-8800 ...
Really? Dual-receive, indeed. And will perform crossband repeating. But I can transmit on one band and simultaneously hear myself on another with a FT-8800? _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite
program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Lauren found her dream laptop. Find the PC that’s right for you. http://www.microsoft.com/windows/choosepc/?ocid=ftp_val_wl_290 _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite
program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.339 / Virus Database: 270.12.48/2147 - Release Date: 05/31/09 20:45:00
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
A good discussion of OSCAR III here:
http://projectoscar.files.wordpress.com/2008/03/o3_translator.pdf
Alan WA4SCA
At 05:02 AM 6/3/2009, Martin wrote:
Hi Jim and others.
For ordinary Repeaters the Rx/Tx in the same band is mandatory. But just think of the filtering needed for TX'ing lots og watts just 600kHz away from your Rx-frq. This is also the reason why most repeaters (at least that I know of) uses really big cavity-filters.
Either that or _very_ widely spaces antennas. For example, to avoid the need of rather large cavities, 10m repeaters often use two sites, linked by UHF, to separate Rx and Tx.
But for Rx/Tx on the same frequency - Forget it. What would be the purpose anyway?
Nice way to create a feedback loop. :D You can create an appearance of full duplex by using a high speed switching scheme on a digital transmission. In fact, this is exactly what happens if you run Echolink over a wifi connection. The radio itself is half duplex, single frequency, but the high data rate and fast T/R switching allow full duplex for any VoIP on top of it, at the price of a tiny amount of latency.
In my terms, a full-duplex radio is a radio that listens on one band, whilst transmitting on another.
Nope, full duplex refers to any communication channel capable of transmitting and receiving information simultaneously. While I know of no radio capable of running full duplex on the same frequency, as someone pointed out, the humble analog (landline) telephone does exactly that.
73 de VK3JED / VK3IRL http://vkradio.com
participants (12)
-
Alan P. Biddle -
Andrew Glasbrenner -
Clint Bradford -
Ernie -
Greg D. -
Jim Heck -
Martin -
Nate Duehr -
Nigel Gunn G8IFF/W8IFF -
OZ1MY -
Patrick STODDARD (WD9EWK/VA7EWK) -
Tony Langdon