Thats low budget? if so I am jealous
Despite my earlier concerns about having the “without attenuator” version of the transverter, it seems to be working well.
I tested it on transmit into a dummy load using a hard-wired PTT cable I made linking the Key Out from the KX2 to the PTT input on the XVR. I found adjusting the XVR’s RV1 potentiometer at the IF input had a very non-linear effect on XVR power output. Over a very small adjustment range it went from ~1W (on CW) to about 12-15W. Managed to get a ‘sweet spot’ where the CW output is about 8-10W (as in the photo).
Also, I adjusted the VOX-delay on the KX2 to about 200ms to stop the XVR switching back to Rx between dots and dashes just in case the KX2 and XVR aren’t completely in Rx-Tx sync.
It’s transmitting correctly in CW mode. I tried calling CW and SSB for reports but no luck but had two FM QSOs with good signal and audio reports.
So, the transverter seems to be working well and I’m looking forward to taking it on my next SOTA activation for more 2m-CW and 2m-SSB field testing.
It’s certainly not low budget if you are starting from scratch!
But if you happen to own a 10M rig already, $95 to add 2M is not so bad. (or as little as $35 if you just buy the transverter board)
Icom cant do this. It was a real fiddle to get a external amp with preamp going on my IC910H with out blowing up the preamp FET.
But it is a pity that there is so little going on ssb.
DL1CR’s just qualified DM/NS-122 easily on 144 MHz SSB.
Are there any AE (Aircraft Enhancement) operators in you part of the world? In VK1/2/3/4/5/7 there’s a morning 0800 local, group that are very active on 2m SSB. I have qualified a summit with them using AE. Pretty simple get under a flight path and use a Slim Jim and pull it over horizontal to get a few extra dB.
Oh yes, and aircraft scatter is even predictable: Air Scout by DL2ALF. However, I’ve never heard of deliberate SOTA AS contacts*.
Hmm, anybody for a 144 MHz AS s2s event?
*On 144MHz. DL4MFM made some QSO’s on 23 cm AS.
This sounds tempting to me, as I live near a drive up 4 pointer SOTA which has a VOR on its summit and dozens of aircrafts each day follow different routes passing all of them above this summit.
I confess I’ve almost never used 2m SSB so I’ve no experience of these type of contacts.
I have an FT-817 and also have a Daiwa 2m preamp + power amp which produces around 30W (I believe) under a 5W input.
Will it be possible to make an AE contact with a colineal GP in horizontal and just the 5W of my FT-817 or it will be necessary the use of the amplifier?
How about this for a super lightweight 2 metre tx/rx antenna? A PCB based 2 metre magnetic loop. Available from FunkAmateur (Box73) as a kit for €12 plus shipping.
It comes with the board, the adjustable capacitor and wire to wind the inductance. The rest of the connectivity is my construction.
It is directional and receives stations that the rubber duck antenna can’t hear from inside the house. I have yet to try it on a summit. In the pictures I have it on a DMR HT but I think it should work in a horizontal configuration on an SSB rig as well.
Checks out fine on the NanoVNA as well (you need something like that to tune it to frequency).
Not bad for 10 W on 2m and 4 elements LogPer.
O.K., the SM had 4 over 12 elements, but I enjoy his good modulation rapport of my KX2 and 2m transverter.
How refreshing to see that the “VHF is Alive and Well” v “VHF is dead and buried” debate has a DL section.
Actually there are encouraging signs that 2m is emerging from its long torpor at last in my area, so I am cancelling my subscription to the “Dead and Buried” club!
Thanks for the info and starting the thread Armin, I managed to get one myself for the KX2 and hope to give a go from the garden tomorrow.
An important issue when using any external transverter is to manage the power level it is driven with. It is vital to set the driver radio to produce no more than the power level required and accepted by the transverter, otherwise components in the transverter can be damaged. It is possible to set the kx2/3 power level way below the default levels available on the power control, I found an article from one of the Elecraft founders on the group Air-Ham on groups.io. You wouldn’t want that detailed process to be required whenever switching from an HF band to the VHF (via transverter), so if the transverter is set to accept a reasonable power level like 0.5 to 1 watt, that will be far more convenient when switching bands. Mistakes happen on summits, so I’d recommend considering how to fool-proof the power level setting.
73 Andrew VK1DA/VK2UH
This is exactly why I am still hung up on my FT-817ND. Not only is it one of the few portable radios that has all-mode 2m and 70cm included, but it also has a 0.5W (500 mw or 1/2-watt) output that is perfect for saving the battery and driving transverters. In my opinion, this was one of the things they screwed up with the FT-818, there is no longer a 1/2-watt level.
I am waiting to see how the new ICOM IC-705 shakes out. That may do what all the others failed to do, that is to replace the FT-817ND.
Vy73 – Mike --KD5KC-- El Paso, Texas.
That’s an interesting matter, but does anyone know whether the 818 has the same software-controlled power level settings as the 817? If so, it is a matter of a simple power level change for the lowest power level of the band used for the transverter. Realignment of that power level should be done using decent test equipment and follow the process in the Yaesu service manual, other than the power level being chosen for the lowest power setting.
I suggest a close examination of the recommended power input from the HF rig for that transverter. It may be limited by a few half watt resistors in the attenuator, typically needed to reduce the power level to as low as 0 dbm or 1 milliwatt for input to a typical mixer. Feeding 5 or 10 watts to an attenuator circuit intended to accept only 1 watt or less will eventually smoke those resistors and threaten the mixer.
73 Andrew VK1DA/VK2UH
Dunno. The FT-817 series has 0.5, 1, 2.5 and 5 watt levels. The FT-818 has 1, 2.5, 5 and 6 watt levels. 6-watts? Why?
There has been some discussion about getting into the secret menu and trying to make the adjustments. There has also been discussion about changing transverter input resistors to match the FT-818 output.
Since I have two FT-817NDs, and all my gear is working fine, I have no need or desire to buy an FT-818 and start over. There is no doubt that the FT-817/818 design is dated. Show me another radio that has been in production for 20 years and has sold over 250,000 radios. Still, anyone who makes a battery powered QRP radio that covers all-mode 160m-70cm will likely kill the FT-817. Yaesu has said they will not replace the FT-817/818 until sales fall off. Maybe the IC-705 can do what the KX3 could not. I would like a “better radio”. But not if I have to give up 2m and 70cm.
Vy73 – Mike – KD5KC – El Paso, Texas.
only someone in the Yaesu design team could tell us the rationale for the power levels. I could suggest some ideas but it would just be conjecture.
But since the 818 has 4 levels, just as the 817 did, I think it is very likely that the same soft-configured power levels will be there in the service menu. So each could be set to whatever you like. 0.1 or 0.2w if that’s what your transverter needs.
I have two old 817s too. Wouldn’t part with them, though I also really like my IC703 and the newer KX3.
73 Andrew VK1DA/VK2UH
Hi again Andrew.
Oh, I certainly agree that when comparing the FT-817 to the FT-818, it is very likely that someone can enter the secret menu and fix this shortcoming. However, I have two FT-817NDs (the second was sold by a deploying soldier from Fort Bliss at a price that could not be ignored) that drive my little transverters fine. And I do not have an 818 here. To date, I know of no one who has attempted to try changing the power settings on an FT-818.
I am pretty certain that people using the FT-81x radios for serious V/UHF are a smaller subset of owners, and those driving transverters even a lesser number. That said however, the FT-817 is a very popular radio among ROVER stations for the same reason. It is a compact and efficient radio with the capability of driving transverters.
I also have an Icom IC-703+. I use it for a very specialized function - Pedestrian Mobile. I think nearly every Amateur Radio Operator in the world is aware of the USA Field Day event each June. You should find this amusing.
There were 54 mobile stations entered that year. That I finished in 5th place was amazing in any case. But when you see how I did it, this is even more amusing. BTW, some of the places I walked was un-even ground, and while I was able to walk and chew gum at the same time, I had to stand still when sending Morse Code. It wasn’t that my sending suffered so much as it was I nearly fell over a couple of times.
I worked 20-meters during the day, and 40-meters at night. And this is how I did. My location was at the very far left-side of Texas. This was pretty impressive for a QRP radio on a mobile vertical whip dragging a 25 ft (7.5m) wire on the ground behind me.
I am excited to see how the new Icom IC-705 is going to look. Being all-mode and 160m through 70cm, it will truly compete with the Yaesu FT-817/818. I just might have to try one.
You have a SUPER day sir. Since work has requested that us critical employees self-isolate to remain healthy and available, I think today I will install yet another radio in my JEEP.
Vy73 – Mike – KD5KC --El Paso, Texas.