Any experience with low-cost 433MHz transverter from transverters-store?
Hi folks,
I'm trying to get on the air with the linear transponder satellites, and it looks like I need 70cm SSB capability to really get on the air. My Icom IC-796MkII can do SSB on 2m, but not 70cm, so I'm trying to find an affordable way to get 70cm SSB transmit.
Does anybody have experience with these $100 transverter boards from Ukraine? It looks like they're tuned for the weak-signal/SSB end of the band and might require a bit of work to get up to 435MHz for satellites. Is 3-4W enough to be heard?
Eric,
I don't have any experience with that transverter board, or with transverters generally. If you can get the 70cm board to operate at 435-438 MHz, it could be useful for satellite work even at 3 to 4 watts. I regularly work the SSB transponders with a 5W FT-817ND as part of my portable station. If you could get that transverter up toward 4W, it could work as an alternative to a radio like an FT-817ND.
For my portable work, I use short coax runs - 10 feet between antenna (Elk 2m/70cm log periodic) and a 2m/70cm diplexer, and 3-foot runs from the band ports on the diplexer to my transmitter and receiver. Longer coax runs may not be the best for that 3-4W output, and could also require the use of a preamplifier on receive.
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ Twitter: @WD9EWK
On Sun, Jan 31, 2016 at 6:46 PM, Eric Wolak [email protected] wrote:
Hi folks,
I'm trying to get on the air with the linear transponder satellites, and it looks like I need 70cm SSB capability to really get on the air. My Icom IC-796MkII can do SSB on 2m, but not 70cm, so I'm trying to find an affordable way to get 70cm SSB transmit.
Does anybody have experience with these $100 transverter boards from Ukraine? It looks like they're tuned for the weak-signal/SSB end of the band and might require a bit of work to get up to 435MHz for satellites. Is 3-4W enough to be heard?
A question is how is the LO generated. If 432 gives 27, this thing has a 405 MHz LO. Satellite subband is mostly ~435-436. That would require an IF radio to tune ~30-31 MHz. Most don't. If the LO is crystal controlled, changing crystals is ridiculously expensive; like $40-60. Not a great value. The LO could be synthesized and might be modifyable. Maybe. I would write to the seller and ask if the LO can be changed.
Ed Krome K9EK Sent from my iPhone
On Jan 31, 2016, at 1:46 PM, Eric Wolak [email protected] wrote:
Hi folks,
I'm trying to get on the air with the linear transponder satellites, and it looks like I need 70cm SSB capability to really get on the air. My Icom IC-796MkII can do SSB on 2m, but not 70cm, so I'm trying to find an affordable way to get 70cm SSB transmit.
Does anybody have experience with these $100 transverter boards from Ukraine? It looks like they're tuned for the weak-signal/SSB end of the band and might require a bit of work to get up to 435MHz for satellites. Is 3-4W enough to be heard?
http://www.ebay.com/itm/221871269275 _______________________________________________ Sent via [email protected]. 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. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
The transverter itself can cover the satellite portion of the band. The specs say it covers 432 - 442 MHz. The issue is that your IF radio, the Icom IC-706MkII is what I believe you meant to say, can tune high enough on the 10M band and above for RECEPTION at the appropriate frequencies, but will not transmit above 30 MHz and therefore, through this transverter, will not transmit above 435.0000 MHz. I know this from experience with my 222 MHz transverter. Fortunately, on that band, 28-30 MHz -> 222-224 MHz, and the portion of the band above that (224-225 MHz) is mostly FM repeater OUTPUTS, which the radio will happily receive through my transverter.
What you would need to do is defeat the 10M band transmit limits on your IC-706MkII. You can probably find mods to allow that.
Your other issue, which I also had to overcome with my 222 transverter, is that the transverter needs (accepts) only a very low RF power signal on transmit (1-100 milliwatts) and your IC-706MkII is happy to transmit 1000 times as much power, up to 100 watts. So you will need to carefully interface the radio to the transverter to insure that the transmit power is nice and low. In my case, my transverter interface includes a source of negative voltage to feed into the ALC input of the radio, which can drop the power low enough. Interesting (=undesirable) things happen if this ALC circuit fails, or more likely, gets accidentally disconnected. I was fortunate, when I transmitted 100 watts into my transverter by accident, I only fried a 50 ohm resistor in the input circuit, and after replacing it, all was good again, The same may or may not hold with this transverter.
Good luck in your search for a solution.
John Toscano, W0JT/5
On Sun, Jan 31, 2016 at 12:46 PM, Eric Wolak [email protected] wrote:
Hi folks,
I'm trying to get on the air with the linear transponder satellites, and it looks like I need 70cm SSB capability to really get on the air. My Icom IC-796MkII can do SSB on 2m, but not 70cm, so I'm trying to find an affordable way to get 70cm SSB transmit.
Does anybody have experience with these $100 transverter boards from Ukraine? It looks like they're tuned for the weak-signal/SSB end of the band and might require a bit of work to get up to 435MHz for satellites. Is 3-4W enough to be heard?
http://www.ebay.com/itm/221871269275 _______________________________________________ Sent via [email protected]. 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. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Thanks, guys! It looks like the transverter kit includes an attenuator board to interface with a radio, so I'm set on that. These transponders work both ways, right, so if I can TX on 2m and RX on 70cm (through the transverter), then I can hear my own transmissions full-duplex, and I can make contact with someone TX'ing on 70cm?
Are there any attributes that might be lacking with such a low-cost option, e.g. frequency stability or harmonics?
On Sun, Jan 31, 2016, at 03:12 PM, John Toscano wrote:
The transverter itself can cover the satellite portion of the band. The specs say it covers 432 - 442 MHz. The issue is that your IF radio, the Icom IC-706MkII is what I believe you meant to say, can tune high enough on the 10M band and above for RECEPTION at the appropriate frequencies, but will not transmit above 30 MHz and therefore, through this transverter, will not transmit above 435.0000 MHz. I know this from experience with my 222 MHz transverter. Fortunately, on that band, 28-30 MHz -> 222-224 MHz, and the portion of the band above that (224-225 MHz) is mostly FM repeater OUTPUTS, which the radio will happily receive through my transverter.
What you would need to do is defeat the 10M band transmit limits on your IC-706MkII. You can probably find mods to allow that.
Your other issue, which I also had to overcome with my 222 transverter, is that the transverter needs (accepts) only a very low RF power signal on transmit (1-100 milliwatts) and your IC-706MkII is happy to transmit 1000 times as much power, up to 100 watts. So you will need to carefully interface the radio to the transverter to insure that the transmit power is nice and low. In my case, my transverter interface includes a source of negative voltage to feed into the ALC input of the radio, which can drop the power low enough. Interesting (=undesirable) things happen if this ALC circuit fails, or more likely, gets accidentally disconnected. I was fortunate, when I transmitted 100 watts into my transverter by accident, I only fried a 50 ohm resistor in the input circuit, and after replacing it, all was good again, The same may or may not hold with this transverter.
Good luck in your search for a solution.
John Toscano, W0JT/5
On Sun, Jan 31, 2016 at 12:46 PM, Eric Wolak [email protected] wrote:
Hi folks,
I'm trying to get on the air with the linear transponder satellites, and it looks like I need 70cm SSB capability to really get on the air. My Icom IC-796MkII can do SSB on 2m, but not 70cm, so I'm trying to find an affordable way to get 70cm SSB transmit.
Does anybody have experience with these $100 transverter boards from Ukraine? It looks like they're tuned for the weak-signal/SSB end of the band and might require a bit of work to get up to 435MHz for satellites. Is 3-4W enough to be heard?
http://www.ebay.com/itm/221871269275 _______________________________________________ Sent via [email protected]. 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. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
I'm working on a 2 meter one of those units here.
Now the only somewhat negative thing I have heard about the 2 meter version, ( so do not know if it applies to the 70 cm one ) Is if you run it near it's rated max output it gets kind of dirty. https://youtu.be/w8JQ0SIUlI8
Joe WB9SBD Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com On 2/1/2016 11:06 PM, Eric Wolak wrote:
Thanks, guys! It looks like the transverter kit includes an attenuator board to interface with a radio, so I'm set on that. These transponders work both ways, right, so if I can TX on 2m and RX on 70cm (through the transverter), then I can hear my own transmissions full-duplex, and I can make contact with someone TX'ing on 70cm?
Are there any attributes that might be lacking with such a low-cost option, e.g. frequency stability or harmonics?
On Sun, Jan 31, 2016, at 03:12 PM, John Toscano wrote:
The transverter itself can cover the satellite portion of the band. The specs say it covers 432 - 442 MHz. The issue is that your IF radio, the Icom IC-706MkII is what I believe you meant to say, can tune high enough on the 10M band and above for RECEPTION at the appropriate frequencies, but will not transmit above 30 MHz and therefore, through this transverter, will not transmit above 435.0000 MHz. I know this from experience with my 222 MHz transverter. Fortunately, on that band, 28-30 MHz -> 222-224 MHz, and the portion of the band above that (224-225 MHz) is mostly FM repeater OUTPUTS, which the radio will happily receive through my transverter.
What you would need to do is defeat the 10M band transmit limits on your IC-706MkII. You can probably find mods to allow that.
Your other issue, which I also had to overcome with my 222 transverter, is that the transverter needs (accepts) only a very low RF power signal on transmit (1-100 milliwatts) and your IC-706MkII is happy to transmit 1000 times as much power, up to 100 watts. So you will need to carefully interface the radio to the transverter to insure that the transmit power is nice and low. In my case, my transverter interface includes a source of negative voltage to feed into the ALC input of the radio, which can drop the power low enough. Interesting (=undesirable) things happen if this ALC circuit fails, or more likely, gets accidentally disconnected. I was fortunate, when I transmitted 100 watts into my transverter by accident, I only fried a 50 ohm resistor in the input circuit, and after replacing it, all was good again, The same may or may not hold with this transverter.
Good luck in your search for a solution.
John Toscano, W0JT/5
On Sun, Jan 31, 2016 at 12:46 PM, Eric Wolak [email protected] wrote:
Hi folks,
I'm trying to get on the air with the linear transponder satellites, and it looks like I need 70cm SSB capability to really get on the air. My Icom IC-796MkII can do SSB on 2m, but not 70cm, so I'm trying to find an affordable way to get 70cm SSB transmit.
Does anybody have experience with these $100 transverter boards from Ukraine? It looks like they're tuned for the weak-signal/SSB end of the band and might require a bit of work to get up to 435MHz for satellites. Is 3-4W enough to be heard?
http://www.ebay.com/itm/221871269275 _______________________________________________ Sent via [email protected]. 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. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. 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. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
No, if you are using an Icom IC-706MkII as your IF radio, it cannot operate in full duplex mode. It CAN do split-band Tx/Rx, where you receive with the built-in 2M section and transmit on 10 meters into the transverter to get 70 cm output. Or you can receive on 10 meters which becomes 70cm through the transverter, and transmit on the built-in 2M section of the radio. But you can't hear while transmitting. You would need a second radio or a radio that is designed for full-duplex operation.
If you could find a deal on another IC-706MkII and add the 70cm transverter to it, you'd then have a full-duplex station. A less expensive choice might be an IC-703, which lacks the 2M band, but you only need 10M to run the transverter anyway, so it would still make a nice matching pair of radios that would work well for satellites. Or if you could find an IC-706MkIIg then you'd have a nicely matching pair that includes 70cm on the new radio and you'd use 2M on the older radio. Kind of pricey, but it's just a couple of suggestions that could be made to work.
Another popular choice is a Yaesu FT-817. But then you would not need a transverter since it has both 2M and 70cm bands already. You just might need a PA to output more than 5 watts on mode UV, but no extra PA needed for mode VU since the transmitter is the IC-706MkII in that mode.
Choces, choices, choices... And we didn't even get into full-duplex radios like a Yaesu FT-847. (I love mine!)
Happy shopping. John, W0JT/5
On Mon, Feb 1, 2016 at 11:06 PM, Eric Wolak [email protected] wrote:
Thanks, guys! It looks like the transverter kit includes an attenuator board to interface with a radio, so I'm set on that. These transponders work both ways, right, so if I can TX on 2m and RX on 70cm (through the transverter), then I can hear my own transmissions full-duplex, and I can make contact with someone TX'ing on 70cm?
Are there any attributes that might be lacking with such a low-cost option, e.g. frequency stability or harmonics?
On Sun, Jan 31, 2016, at 03:12 PM, John Toscano wrote:
The transverter itself can cover the satellite portion of the band. The specs say it covers 432 - 442 MHz. The issue is that your IF radio, the Icom IC-706MkII is what I believe you meant to say, can tune high enough on the 10M band and above for RECEPTION at the appropriate frequencies, but will not transmit above 30 MHz and therefore, through this transverter, will not transmit above 435.0000 MHz. I know this from experience with my 222 MHz transverter. Fortunately, on that band, 28-30 MHz -> 222-224 MHz, and the portion of the band above that (224-225 MHz) is mostly FM repeater OUTPUTS, which the radio will happily receive through my transverter.
What you would need to do is defeat the 10M band transmit limits on your IC-706MkII. You can probably find mods to allow that.
Your other issue, which I also had to overcome with my 222 transverter, is that the transverter needs (accepts) only a very low RF power signal on transmit (1-100 milliwatts) and your IC-706MkII is happy to transmit 1000 times as much power, up to 100 watts. So you will need to carefully interface the radio to the transverter to insure that the transmit power is nice and low. In my case, my transverter interface includes a source of negative voltage to feed into the ALC input of the radio, which can drop the power low enough. Interesting (=undesirable) things happen if this ALC circuit fails, or more likely, gets accidentally disconnected. I was fortunate, when I transmitted 100 watts into my transverter by accident, I only fried a 50 ohm resistor in the input circuit, and after replacing it, all was good again, The same may or may not hold with this transverter.
Good luck in your search for a solution.
John Toscano, W0JT/5
On Sun, Jan 31, 2016 at 12:46 PM, Eric Wolak [email protected] wrote:
Hi folks,
I'm trying to get on the air with the linear transponder satellites, and it looks like I need 70cm SSB capability to really get on the air. My Icom IC-796MkII can do SSB on 2m, but not 70cm, so I'm trying to find an affordable way to get 70cm SSB transmit.
Does anybody have experience with these $100 transverter boards from Ukraine? It looks like they're tuned for the weak-signal/SSB end of the band and might require a bit of work to get up to 435MHz for satellites. Is 3-4W enough to be heard?
http://www.ebay.com/itm/221871269275 _______________________________________________ Sent via [email protected]. 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. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. 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. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Ahhh, right. I still only have one SSB modulator/demodulator, no matter how I slice it. Back to the RTLSDR stick!
On Tue, Feb 2, 2016, at 12:19 PM, John Toscano wrote:
No, if you are using an Icom IC-706MkII as your IF radio, it cannot operate in full duplex mode. It CAN do split-band Tx/Rx, where you receive with the built-in 2M section and transmit on 10 meters into the transverter to get 70 cm output. Or you can receive on 10 meters which becomes 70cm through the transverter, and transmit on the built- in 2M section of the radio. But you can't hear while transmitting. You would need a second radio or a radio that is designed for full-duplex operation.
If you could find a deal on another IC-706MkII and add the 70cm transverter to it, you'd then have a full-duplex station. A less expensive choice might be an IC-703, which lacks the 2M band, but you only need 10M to run the transverter anyway, so it would still make a nice matching pair of radios that would work well for satellites. Or if you could find an IC-706MkIIg then you'd have a nicely matching pair that includes 70cm on the new radio and you'd use 2M on the older radio. Kind of pricey, but it's just a couple of suggestions that could be made to work.
Another popular choice is a Yaesu FT-817. But then you would not need a transverter since it has both 2M and 70cm bands already. You just might need a PA to output more than 5 watts on mode UV, but no extra PA needed for mode VU since the transmitter is the IC-706MkII in that mode.
Choces, choices, choices... And we didn't even get into full-duplex radios like a Yaesu FT-847. (I love mine!)
Happy shopping. John, W0JT/5
On Mon, Feb 1, 2016 at 11:06 PM, Eric Wolak [email protected] wrote:
Thanks, guys! It looks like the transverter kit includes an attenuator
board to interface with a radio, so I'm set on that. These transponders
work both ways, right, so if I can TX on 2m and RX on 70cm (through the
transverter), then I can hear my own transmissions full-duplex, and I
can make contact with someone TX'ing on 70cm?
Are there any attributes that might be lacking with such a low-cost
option, e.g. frequency stability or harmonics?
On Sun, Jan 31, 2016, at 03:12 PM, John Toscano wrote:
The transverter itself can cover the satellite portion of the band.
The specs say it covers 432 - 442 MHz. The issue is that your IF
radio, the Icom IC-706MkII is what I believe you meant to say, can
tune high enough on the 10M band and above for RECEPTION at the
appropriate frequencies, but will not transmit above 30 MHz and
therefore, through this transverter, will not transmit above 435.0000
MHz. I know this from experience with my 222 MHz transverter.
Fortunately, on that band, 28-30 MHz -> 222-224 MHz, and the portion
of the band above that (224-225 MHz) is mostly FM repeater OUTPUTS,
which the radio will happily receive through my transverter.
What you would need to do is defeat the 10M band transmit limits on
your IC-706MkII. You can probably find mods to allow that.
Your other issue, which I also had to overcome with my 222
transverter, is that the transverter needs (accepts) only a very low
RF power signal on transmit (1-100 milliwatts) and your IC-706MkII is
happy to transmit 1000 times as much power, up to 100 watts. So you
will need to carefully interface the radio to the transverter to
insure that the transmit power is nice and low. In my case, my
transverter interface includes a source of negative voltage to feed
into the ALC input of the radio, which can drop the power low enough.
Interesting (=undesirable) things happen if this ALC circuit fails,
or more likely, gets accidentally disconnected. I was fortunate, when
I transmitted 100 watts into my transverter by accident, I only fried
a 50 ohm resistor in the input circuit, and after replacing it, all
was good again, The same may or may not hold with this transverter.
Good luck in your search for a solution.
John Toscano, W0JT/5
On Sun, Jan 31, 2016 at 12:46 PM, Eric Wolak [email protected] wrote:
Hi folks,
I'm trying to get on the air with the linear transponder satellites,
and it looks like I need 70cm SSB capability to really get on the
air. My Icom IC-796MkII can do SSB on 2m, but not 70cm, so I'm trying
to find an affordable way to get 70cm SSB transmit.
Does anybody have experience with these $100 transverter boards from
Ukraine? It looks like they're tuned for the weak-signal/SSB end of
the band and might require a bit of work to get up to 435MHz for
satellites. Is 3-4W enough to be heard?
http://www.ebay.com/itm/221871269275
Sent via [email protected]. 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. Not an AMSAT-NA member? Join now to
support the amateur satellite program! Subscription settings:
_______________________________________________
Sent via [email protected]. 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.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
participants (5)
-
Ed Krome -
Eric Wolak -
Joe -
John Toscano -
Patrick STODDARD (WD9EWK/VA7EWK)