Re: Protecting (tr)uSDX against high SWR
I'm not saying it's not possible to blow the finals. ? ?
I'm just looking for the side-by-side test or measurements compared to specs on the same radio with and without zener, and am surprised that I am not finding data.
On Fri, Jun 14, 2024 at 18:25, Doug Hendricks < ki6ds1@...> wrote: Hiroki did it twice.
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Connie KN2EFI
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Re: Protecting (tr)uSDX against high SWR
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Re: Protecting (tr)uSDX against high SWR
Connie,? when you blow your finals. (Not if, but when), I have plenty of replacement transistors,? which are not trivial to remove.? Lol.
Doug?
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Re: Protecting (tr)uSDX against high SWR
Is there a side-by-side test documented anywhere???? Ie, showing that the radio is destroyed without the zener diode under the same conditions otherwise??? I couldn't find one.?? They're cheap -- you'd think someone would love to blow one up for the views.
I've done a little searching and all I can find as the origin for this recommendation is just one guy with a self-assembled kit who blew his radio up in an unknown way with unknown power even though he had a tuner inline and was presumably tuned up, and he doesn't know what the root cause was, and then said he'd install the zener just in case.
As for WB2CBA (Barb), he just shows that his radio still works.? He didn't do a side-by-side test.??? And it's not a TruSDX.?? Maybe he could have painted it blue or stuck a bandaid to the back of the radio instead and shown that the radio still worked after a high-swr test.?? Look!?? Painting it blue works!
DL2MAN recommends against adding the zener.?? (His recommendation is boring, just use low power for tuning.? Personally I tune by ear before any kind of tx'ing.?? Works great if you have the ear and the tuner.) ?? Also I had a friend (sadly SK now) who gave his TruSDX a hard workout for a good while and told me that it was pretty robust against mismatch.
I don't think "voltage reflected back into the radio" is exactly the problem with mismatched impedances anyway so maybe the zener works, but maybe not for its breakdown threshold; maybe it just changes the tuning.?? Or maybe it works as well as a bandaid.??? Gotta show me some measurements or a side-by-side test before I'm convinced.??
For all of these reasons, and the fact that it's a cheap radio, and any mod activity introduces unknown risk (which is why regression testing exists), I think I'll save myself the trouble for now. ? I am still open to to the idea and interested to see if any more evidence comes in, in which case it's easy enough to add the zener.???? Or if I blow up this radio in which case you can give me a good Nelson "haha!"?? (Simpsons reference)
73,
Connie? W6EFI
Connie Stillinger
650-380-2018
On Friday, June 14th, 2024 at 10:37 AM, Doug Hendricks <ki6ds1@...> wrote:
Thank you Hiroki for your validation.? ?I heartedly encourage everyone who has usdx radios,? including the one from Ed Fong to do this simple mod.
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Connie KN2EFI
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I drove home from Chester yesterday, and am pretty tired.? I hope to see you all next week. 73, Eric NF6S
ex WD6DBM
?
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Re: Protecting (tr)uSDX against high SWR
Thank you Hiroki for your validation.? ?I heartedly encourage everyone who has usdx radios,? including the one from Ed Fong to do this simple mod.
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Protecting (tr)uSDX against high SWR
I installed a Zenar diode to protect my (tr)uSDX against high SWR and replicated the same experiment conducted by Barb WB2CBA (the video I forwarded to this forum a while ago).
With a dummy load the (tr)uSDX shows 2.97 watt output and SWR 1.1. Without the dummy load SWR shot up to 101.5 but no smoke or visible damage.?
The third photo shows how the diode was installed in my XH2 (you remember the Poor Man¡¯s KH1?) which is made from a Hi-band (tr)uSDX kit.
So I am totally convinced that a single Zenar diode does protect your (tr)uSDX and other USDX radios.
Hiroki AH6CY
  
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Re: I¡¯m doing a little survey of people that have rotatable antennas.
Consider grey paint, less visible
toggle quoted message
Show quoted text
On Jun 14, 2024, at 7:44?AM, Cliff Sojourner K6CLS via groups.io <cls@...> wrote:
Joy, about painting;
Any kind of enamel will work to protect the fiberglass rods from UV.
Go to OSH and get a big can of their brand spray black enamel.? Gloss or flat, your choice; heck you can use white or green or brown if you want.
Details:
If you are not comfortable with spraying and the resulting over spray, get an 8oz can of enamel and a brush.
The fiberglass likely has some mold release (PVA) on it from the factory.?? You can feel it, it's a little slippery.? It?? is best removed chemically, I use Zep brand orange degreaser spray.? The fiberglass will be squeaky clean.
If the rods have any splinters (be careful!) those can be tamed.? use a green Scotch Brite scrubby and some water.
Cliff K6CLS CM87 On June 14, 2024 7:10:03 AM PDT, Joy Rabins <doghouse3@...> wrote:
Paul, The way my "MacLogger DX" logging program works is, it gives you a spreadsheet like list of spots from its spot cluster. When I select a spot from this list, it tunes the radio to the selected frequency and mode that is displayed on the cluster list. I think the way it works is if you have a third party controller connected, in addition to switching to the correct band and mode it would also turn the rotor to that spot information listed as their address from the spot. I think it gets most of the ?information from QRZ. Now, if the cluster spot that is selected ?is the home address coordinates, and they are working portable somewhere, all bets are off and it won't work because the rotor control will be turning the antenna to the home address ?coordinates listed in QRZ which will be wrong........unless of course, they are working portable from their backyard ;)?
This is more than I probably need to get started and can always add it later.?
This is all new to me. I have never even seen a station that has rotor set up in action, hence all the questions.?
The hex beam arrived yesterday. I don't know exactly what I was expecting but i thought it would be in a lot bigger package. But most of it is air when it's deployed.
Dick told me to make sure I painted the spreaders before it goes up. The KIO website suggested Rustoleum black flat spray paint- two coats. Have you ever looked at the Rustoleum ?website? Even if I choose black for a color, they have a gazillion choices of products. Everything from painting motors to plastic. I sent their product support a message asking which product to use to paint fiberglass, so I'm waiting for their responce. Once this baby goes up......it is not coming down because I used the wrong paint.?
Expect more questions.
Joy
N6GO
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Re: I¡¯m doing a little survey of people that have rotatable antennas.
Joy, about painting;
Any kind of enamel will work to protect the fiberglass rods from UV.
Go to OSH and get a big can of their brand spray black enamel.? Gloss or flat, your choice; heck you can use white or green or brown if you want.
Details:
If you are not comfortable with spraying and the resulting over spray, get an 8oz can of enamel and a brush.
The fiberglass likely has some mold release (PVA) on it from the factory.?? You can feel it, it's a little slippery.? It?? is best removed chemically, I use Zep brand orange degreaser spray.? The fiberglass will be squeaky clean.
If the rods have any splinters (be careful!) those can be tamed.? use a green Scotch Brite scrubby and some water.
Cliff K6CLS CM87
On June 14, 2024 7:10:03 AM PDT, Joy Rabins <doghouse3@...> wrote:
Paul, The way my "MacLogger DX" logging program works is, it gives you a spreadsheet like list of spots from its spot cluster. When I select a spot from this list, it tunes the radio to the selected frequency and mode that is displayed on the cluster list. I think the way it works is if you have a third party controller connected, in addition to switching to the correct band and mode it would also turn the rotor to that spot information listed as their address from the spot. I think it gets most of the ?information from QRZ. Now, if the cluster spot that is selected ?is the home address coordinates, and they are working portable somewhere, all bets are off and it won't work because the rotor control will be turning the antenna to the home address ?coordinates listed in QRZ which will be wrong........unless of course, they are working portable from their backyard ;)?
This is more than I probably need to get started and can always add it later.?
This is all new to me. I have never even seen a station that has rotor set up in action, hence all the questions.?
The hex beam arrived yesterday. I don't know exactly what I was expecting but i thought it would be in a lot bigger package. But most of it is air when it's deployed.
Dick told me to make sure I painted the spreaders before it goes up. The KIO website suggested Rustoleum black flat spray paint- two coats. Have you ever looked at the Rustoleum ?website? Even if I choose black for a color, they have a gazillion choices of products. Everything from painting motors to plastic. I sent their product support a message asking which product to use to paint fiberglass, so I'm waiting for their responce. Once this baby goes up......it is not coming down because I used the wrong paint.?
Expect more questions.
Joy
N6GO
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Re: I¡¯m doing a little survey of people that have rotatable antennas.
Paul, The way my "MacLogger DX" logging program works is, it gives you a spreadsheet like list of spots from its spot cluster. When I select a spot from this list, it tunes the radio to the selected frequency and mode that is displayed on the cluster list. I think the way it works is if you have a third party controller connected, in addition to switching to the correct band and mode it would also turn the rotor to that spot information listed as their address from the spot. I think it gets most of the ?information from QRZ. Now, if the cluster spot that is selected ?is the home address coordinates, and they are working portable somewhere, all bets are off and it won't work because the rotor control will be turning the antenna to the home address ?coordinates listed in QRZ which will be wrong........unless of course, they are working portable from their backyard ;)?
This is more than I probably need to get started and can always add it later.?
This is all new to me. I have never even seen a station that has rotor set up in action, hence all the questions.?
The hex beam arrived yesterday. I don't know exactly what I was expecting but i thought it would be in a lot bigger package. But most of it is air when it's deployed.
Dick told me to make sure I painted the spreaders before it goes up. The KIO website suggested Rustoleum black flat spray paint- two coats. Have you ever looked at the Rustoleum ?website? Even if I choose black for a color, they have a gazillion choices of products. Everything from painting motors to plastic. I sent their product support a message asking which product to use to paint fiberglass, so I'm waiting for their responce. Once this baby goes up......it is not coming down because I used the wrong paint.?
Expect more questions.
Joy
N6GO
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Re: I¡¯m doing a little survey of people that have rotatable antennas.
Joy,
Old-school since it went up 30 years ago 73, Eric NF6S
ex WD6DBM
?
On Thu, Jun 13, 2024 at 12:43 PM, Joy Rabins <doghouse3@...> wrote: Do you just use the controller that comes with the rotor to exclusivity rotate your antenna,? or do you add a third party box that allows you to have the? computer control your rotor with your logging software??
Thanks,?
Joy?
N6GO
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Re: I¡¯m doing a little survey of people that have rotatable antennas.
I use the makers rotor controllers.? One less cable, plus computer to configure.
Besides, the computer logger can't guess what station you are trying to work until you are ready to log the QSO.?
On any band below 2 meters.? 30 degree pointing is close to perfect.
On Thursday, June 13, 2024 at 12:43:55 PM PDT, Joy Rabins <doghouse3@...> wrote:
Do you just use the controller that comes with the rotor to exclusivity rotate your antenna,? or do you add a third party box that allows you to have the? computer control your rotor with your logging software??
Thanks,?
Joy?
N6GO
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I¡¯m doing a little survey of people that have rotatable antennas.
Do you just use the controller that comes with the rotor to exclusivity rotate your antenna,? or do you add a third party box that allows you to have the? computer control your rotor with your logging software??
Thanks,?
Joy?
N6GO
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I plan to be there for lunch but I will have to leave afterwards.?
Joy
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Even the Martians are feeling it
If you are having problems with the bands, so are the hams on Mars.?It appears that even ET8 has been affected. Here is probably the reason.?
| | Mars scientists have been anticipating epic solar storms ever since the sun entered a period of peak activity earlier this year. This peak in the 11-year cycle is called solar maximum (.) Over the past month, NASA¡¯s Mars rovers and orbiters have provided researchers with front-row seats to a series of solar flares and coronal mass ejections () that have reached Mars, in some cases, even causing Martian auroras.?.
EarthSky News |
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I plan to be at the Baylands starting with lunch. Hope to see many of you.
Hiroki AH6CY
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I wouldn't discourage you from adding it. If it shorts, it's easier to replace than a FET, cheaper?too. --Jeff
On Tue, Jun 11, 2024 at 11:19?AM Doug Hendricks via <ki6ds1= [email protected]> wrote: And can anyone give me a reason not to install the diode?? I'm trying to learn?
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I've been in chester the past several weeks, and the blustery winds kept me from putting up antennas.? The road thru lassen is not yet plowed, so no hf or vhf ops for me.??
As Cliff mentioned, nearly all 6m activity is ft8 on 50.313, and despite calling CQ on the SSB and CW freqs during openings, they are nearly dead.? This is a far cry from the old days when we left our 6m rigs squelched on the calling freq, and when 6m opened, it was like 50 people shouting at once all of a sudden.??
If I make it back this week, I hope to see you on Friday.??
On Tue, Jun 11, 2024 at 3:27 PM, Cliff Sojourner K6CLS via groups.io <cls@...> wrote: Last Saturday during the VHF contest I heard some ops on 2m QSY to 6m, fm, 52.525.? so that's 2.? Otherwise, yeah all the action is FT8, 50.313.? no CW, SSB, AM.? Shame, waste of 4MHz.
Contest wise, the strategy is to make 6m QSOs to get grids for score multipliers.? 6m is worth only 1 point, so spend most of the time on higher bands, 2 and 4 point QSOs.
That said... What if they gave a contest and nobody came?? Saturday was ghostly, very little action.? Sunday we made oatmeal cookies instead.
Cliff K6CLS CM87 On June 11, 2024 12:59:14 AM PDT, "David via groups.io" <dkvarn@...> wrote:
...meters, that is. I have a vintage Heathkit SB-110A 6-meter transceiver that I purchased c. 2000 and am considering selling on ePay. I was hoping to get it going for the first time this past weekend (I have a pretty good rig backlog) and using it on SSB during the ARRL VHF Contest. I did the usual vintage rig prep. Unfortunately the transmit section seem kaput, but the receive section seems to be working.?
I did not hear the expected SSB signals--did any of y'all? I did hear tones around 50.16 and 50.31 MHz--I understand the latter is FT8, yes? As to the former, online info indicates that it is used by Radio Scouts / Jamboree on the Air, JOTA. Anybody familiar with that?
A member recently mentioned that to test an SSB transmitter, one could use a phone app to generate FT8 audio, play the phone's audio into the mic of the transmitter and use PSK Reporter as a reverse beacon.?
How about the inverse, i.e., play FT8 audio through an SSB rig's speaker and use a phone app to listen and decode the FT8 signal (?) I could more fully verify the SB-110A's receiver operation that way.
I'm also thinking of doing a video including the received FT8 audio and posting the video in the eBay listing.
Thanks, and best, --David KM6RI
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Last Saturday during the VHF contest I heard some ops on 2m QSY to 6m, fm, 52.525.? so that's 2.? Otherwise, yeah all the action is FT8, 50.313.? no CW, SSB, AM.? Shame, waste of 4MHz.
Contest wise, the strategy is to make 6m QSOs to get grids for score multipliers.? 6m is worth only 1 point, so spend most of the time on higher bands, 2 and 4 point QSOs.
That said... What if they gave a contest and nobody came?? Saturday was ghostly, very little action.? Sunday we made oatmeal cookies instead.
Cliff K6CLS CM87
On June 11, 2024 12:59:14 AM PDT, "David via groups.io" <dkvarn@...> wrote:
...meters, that is. I have a vintage Heathkit SB-110A 6-meter transceiver that I purchased c. 2000 and am considering selling on ePay. I was hoping to get it going for the first time this past weekend (I have a pretty good rig backlog) and using it on SSB during the ARRL VHF Contest. I did the usual vintage rig prep. Unfortunately the transmit section seem kaput, but the receive section seems to be working.?
I did not hear the expected SSB signals--did any of y'all? I did hear tones around 50.16 and 50.31 MHz--I understand the latter is FT8, yes? As to the former, online info indicates that it is used by Radio Scouts / Jamboree on the Air, JOTA. Anybody familiar with that?
A member recently mentioned that to test an SSB transmitter, one could use a phone app to generate FT8 audio, play the phone's audio into the mic of the transmitter and use PSK Reporter as a reverse beacon.?
How about the inverse, i.e., play FT8 audio through an SSB rig's speaker and use a phone app to listen and decode the FT8 signal (?) I could more fully verify the SB-110A's receiver operation that way.
I'm also thinking of doing a video including the received FT8 audio and posting the video in the eBay listing.
Thanks, and best, --David KM6RI
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And can anyone give me a reason not to install the diode?? I'm trying to learn?
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Peter Mahowald
Cliff Sojourner K6CLS
Jeff Reagan