Well, we figured out the problem with the 1296 rig, but I'm unsure how to fix the problem. Apparently there has been no oscillation problem all along, the local oscillator chain is producing harmonics that are causing some strange mixing products. We had a strong output on around 1250 mhz that was always at the output anytime the transverter was keyed. This signal goes away when the oscillator is detuned so that it stops oscillating, but is always there anytime the oscillator is going. The signal levels are equal to the desired 1296 signal when driven by the IF rig. So when the rig is running, I had an output on 1296 and a carrier at 1250 (or thereabouts). We traced the problem to a dirty LO chain.
We were able to clean it up substantially by inserting a 3 pole BPF between the 10 mW transverter output and the next amplifier stage. The correct way to fix this in my opinion would be to incorporate another of these filters in the output of the LO chain. We didnt get that far with it today though.
When we hooked up the 2W PA, there was no output from the amp, and we didnt have time to troubleshoot it. It was working when we began testing, so I am guessing it is something simple, such as a short in the RF path somewhere. Since the TX is now clean, I can now troubleshoot the amp and try to maximise the output power.
Another possible problem with the dirty LO is that of receive performance. With a dirty LO, the receiver will be receiving on 2 different frequencies, cutting the gain down by 3dB (or more) on the desired 1296 MHz, and also increasing the noise by 3 dB (or more), I never really noticed a receive problem with the exception of the RF stage oscillating, which was a confirmed problem. So, with that discovery, work can begin cleaning up the LO, and eventually I should get a 1296 rig on the air , hopefully before summer.
Saturday, March 6, 2010
Wednesday, March 3, 2010
1296 Transverter Progress
For quite awhile, I have been battling a low power problem with an older circa 1995 Down East Microwave 1296-144 transverter. At first I thought the PA was blown, I removed it and installed an outboard PA with no success. Eventually I replaced the entire transmit chain with still no improvement.
Most recently, I replaced the mixer IC. The original mixer chip is no longer made, however a newer model which spec's somewhat better than the original was installed.
I never reinstalled the PA module. I am going to do some testing very soon with the +10dBm output from the driver. If everything checks out, I'll continue to use the outboard 2W module, then feed that into the 30W PA. Keeping the rig this way, in my opinion would be more versatile as far as making improvements and upgrades on the circuit. Because everything is interconnected using UT-141 copper hardline, things such as bandpass filters and amplifier replacements can be more easily tried.
I am hoping to put the rig on a spectrum analyser and power meter to determine if the transverter is working properly. If it is, I plan on operating some 1296 up on the Lake, as well as possibly some mountaintop operations this summer. Stay tuned to my blog, I'll report here on the performance once I am able to make the proper tests.
Most recently, I replaced the mixer IC. The original mixer chip is no longer made, however a newer model which spec's somewhat better than the original was installed.
I never reinstalled the PA module. I am going to do some testing very soon with the +10dBm output from the driver. If everything checks out, I'll continue to use the outboard 2W module, then feed that into the 30W PA. Keeping the rig this way, in my opinion would be more versatile as far as making improvements and upgrades on the circuit. Because everything is interconnected using UT-141 copper hardline, things such as bandpass filters and amplifier replacements can be more easily tried.
I am hoping to put the rig on a spectrum analyser and power meter to determine if the transverter is working properly. If it is, I plan on operating some 1296 up on the Lake, as well as possibly some mountaintop operations this summer. Stay tuned to my blog, I'll report here on the performance once I am able to make the proper tests.
Softrock 6.3 RXTX with USB Control
I ordered and built the USB I2C controller board for my Softrock 6.3 RXTX. Adding this option opens up a whole new world for your Softrock. Not only does it allow you to tune the entire bands, but also allows you to have general coverage receive capability with the rig.
It also allows external programs to take control of the radio. This is REALLY cool, as you can run Powersdr in the background and use software such as fldigi and WSPR to actually control the frequency. Fldigi logging works great too, as it can read the frequency of the radio and it puts that into the log automatically.
Another added feature is you no longer need the serial cable to key the transmitter. This is all done now via the USB port. Of course, you still need to set up virtual com ports so the additional software can communicate PTT to Powersdr.
I have been using PowerSDR v.1.19.3.15 with this new setup. This version has been designed for use with CURRENT firmware in your softrock, and it works quite well. I find the audio is less choppy with this version as well, and it's a lot prettier on the screen with its customizable skins.
Upgrading your Softrock with this little $11 board is more than worth adding the option.
On a sidenote, the other night I thought I would try some digital communications running barefoot 1 watt from the radio, and worked a fellow in Arkansas using Olivia 500/16 on 40 meters. I was running 1 watt, he was running 40 watts and was using a Flex-5000. We maintained contact for 1 1/2 hours, talking about SDR in general. Was a real fun QSO. I'm looking forward to working my first Softrock to Softrock rig, as I think that would be quite interesting.
It also allows external programs to take control of the radio. This is REALLY cool, as you can run Powersdr in the background and use software such as fldigi and WSPR to actually control the frequency. Fldigi logging works great too, as it can read the frequency of the radio and it puts that into the log automatically.
Another added feature is you no longer need the serial cable to key the transmitter. This is all done now via the USB port. Of course, you still need to set up virtual com ports so the additional software can communicate PTT to Powersdr.
I have been using PowerSDR v.1.19.3.15 with this new setup. This version has been designed for use with CURRENT firmware in your softrock, and it works quite well. I find the audio is less choppy with this version as well, and it's a lot prettier on the screen with its customizable skins.
Upgrading your Softrock with this little $11 board is more than worth adding the option.
On a sidenote, the other night I thought I would try some digital communications running barefoot 1 watt from the radio, and worked a fellow in Arkansas using Olivia 500/16 on 40 meters. I was running 1 watt, he was running 40 watts and was using a Flex-5000. We maintained contact for 1 1/2 hours, talking about SDR in general. Was a real fun QSO. I'm looking forward to working my first Softrock to Softrock rig, as I think that would be quite interesting.
Saturday, February 13, 2010
Softrock and the Digital Modes
Today I was experimenting with setting up PowerSDR-SR40 for use with fldigi and other digital software, and I got everything talking to each other. When everything is working together, it makes operating digital so easy. So far, I got PSDR working with fldigi and Ham Radio Deluxe. I'm planning on getting it working with MMSSTV and EasyPal Digital SSTV program. I dont think there will be any problems, as they should set up the same as the ones I already got working.
There are 2 programs you will need in order to make everything play nice. First is "Virtual Audio Cable". it can be downloaded from here: http://software.muzychenko.net/eng/vac.html
When you get it, you will need to create 2 virtual sound devices. There are good instructions at the above website on doing this. One will be needed for receive, the other for transmit.
The other program you will need, and you will only need it for software that also controls the radio, such as fldigi and Ham Radio Deluxe, and that is "com0com", This creates virtual com ports to link the control aspects together. It can be gotten here: http://com0com.sourceforge.net/
You will need to create 1 pair of com ports for most applications. There are excellent pdf directions on how to do this at the above website.
Then go into Powersdr and set up the "CAT" section. Although some software will work using the identifier set for "SDR-1000", I've had better luck setting up emulating a TS-2000. Under CAT control, set the com port as the lower com port number that you created in the virtual com ports, I used COM5. Fldigi will use COM6 under its CAT settings. I used RIGCAT in Windows to control the SDR, and it plays nice. I have had some problems getting the external programs to control PTT, so I just use VOX for that. I used to use VOX in my Yaesu too when I ran digi modes.
To get audio to the programs, you need to set up virtual audio cable. I used Virtual Audio Cable #1 for audio out from PSDR and VAC #2 for the TX input audio. These settings will be found in the VAC tab in the audio settings in PSDR. The audio settings in fldigi are just the opposite - VAC2 is the output device, and VAC 1 is the input.
Once everything is talking, fldigi will read the frequency of the radio and you can then use the logger in fldigi, and it works like any other radio would with CAT control.
Ham Radio Deluxe sets up in a similar fashion.
To listen to your receive audio, should you choose to do so, VAC has a little utility called an Audio Repeater. You can set that up to input the proper VAC device as the input, and your soundcard that you use for your speaker audio as the output of the repeater.
There you have it, a basic overview as to how to set up different software so they will talk to eachother. Once they talk, operation is a breeze. I worked a little bit of the RTTY contest, and worked about 25 contacts in less than an hour with only 15 watts of TX power.
Good luck, and I hope this helps you get things working with your Software Defined Radio.
There are 2 programs you will need in order to make everything play nice. First is "Virtual Audio Cable". it can be downloaded from here: http://software.muzychenko.net/eng/vac.html
When you get it, you will need to create 2 virtual sound devices. There are good instructions at the above website on doing this. One will be needed for receive, the other for transmit.
The other program you will need, and you will only need it for software that also controls the radio, such as fldigi and Ham Radio Deluxe, and that is "com0com", This creates virtual com ports to link the control aspects together. It can be gotten here: http://com0com.sourceforge.net/
You will need to create 1 pair of com ports for most applications. There are excellent pdf directions on how to do this at the above website.
Then go into Powersdr and set up the "CAT" section. Although some software will work using the identifier set for "SDR-1000", I've had better luck setting up emulating a TS-2000. Under CAT control, set the com port as the lower com port number that you created in the virtual com ports, I used COM5. Fldigi will use COM6 under its CAT settings. I used RIGCAT in Windows to control the SDR, and it plays nice. I have had some problems getting the external programs to control PTT, so I just use VOX for that. I used to use VOX in my Yaesu too when I ran digi modes.
To get audio to the programs, you need to set up virtual audio cable. I used Virtual Audio Cable #1 for audio out from PSDR and VAC #2 for the TX input audio. These settings will be found in the VAC tab in the audio settings in PSDR. The audio settings in fldigi are just the opposite - VAC2 is the output device, and VAC 1 is the input.
Once everything is talking, fldigi will read the frequency of the radio and you can then use the logger in fldigi, and it works like any other radio would with CAT control.
Ham Radio Deluxe sets up in a similar fashion.
To listen to your receive audio, should you choose to do so, VAC has a little utility called an Audio Repeater. You can set that up to input the proper VAC device as the input, and your soundcard that you use for your speaker audio as the output of the repeater.
There you have it, a basic overview as to how to set up different software so they will talk to eachother. Once they talk, operation is a breeze. I worked a little bit of the RTTY contest, and worked about 25 contacts in less than an hour with only 15 watts of TX power.
Good luck, and I hope this helps you get things working with your Software Defined Radio.
Tuesday, February 9, 2010
SoftRock v6.3 RXTX+Xtall
About 2 weeks ago, I finished building a SoftRock v6.3 RXTX+Xtall SDR transceiver. I ordered the transceiver and 3 power amp, low pass TX filters, so I can cover 80 meters thru 10 meters.
The 6.3 TXRX is a 1 watt PEP transceiver capable of running whatever frequency bands that you supply PA's for. The standard kit allows for 16 presettable (with a 4 section DIP switch) frequencies. Each frequency is tunable over a span of 96 KHz with the software, with the preset dip switch setting being the center of that tuning range. All modes are possible, including SSB, AM, NB FM, and all of the digital modes, including Slow Scan Television using outboard software.
Most of my operation so far has been on WSPR on the 40 meter band, however I have operated SSB on 20 and 40 meters, and have worked a couple of countries using an outboard HFPack amplifier at about 15 watts. The performance is nothing short of remarkable, and have gotten exceptional audio reports while using a VERY cheap computer microphone.
Operating an SDR transceiver requires the use of 2 different sound cards. I use one card that works as the digital signal processor for the radio and the other to drive the speaker on receive and mic for transmit. For the radio card, you want the best sound card you can get, with the lowest noise and highest sample rate. 92 khz sample rate cards are available with noise floors in excess of -100 dB, and they are common and inexpensive. I bought a Soundblaster Audigy card for this purpose, but with many soundblaster internal cards, there is some phase shifting in the card, and I couldnt get a good balance without setting the phase and amplitude all over the place. I've used an older USB card such as the Soundblaster Live external card and that works pretty well. The external cards apparently do not suffer from the phase shifting that the internal cards do.
With the bare transceiver with the fixed frequency settings, the only software that is useable with it is a special version of PowerSDR, called;PowerSDR-SR40 and is available at http://powersdr-sr40.sourceforge.net/. All other versions do not allow you to transmit if the fixed frequency is enabled. There is, however an add on module that allows USB control of the Si570 oscillator that allows continuous tuning, which I ordered but have not received yet.
I will write more stories on this radio, and will detail a little more precisely on setting up this radio for use. It is a fun little rig, and for roughly a $100 investment, you will have yourself a very capable little radio.
The 6.3 TXRX is a 1 watt PEP transceiver capable of running whatever frequency bands that you supply PA's for. The standard kit allows for 16 presettable (with a 4 section DIP switch) frequencies. Each frequency is tunable over a span of 96 KHz with the software, with the preset dip switch setting being the center of that tuning range. All modes are possible, including SSB, AM, NB FM, and all of the digital modes, including Slow Scan Television using outboard software.
Most of my operation so far has been on WSPR on the 40 meter band, however I have operated SSB on 20 and 40 meters, and have worked a couple of countries using an outboard HFPack amplifier at about 15 watts. The performance is nothing short of remarkable, and have gotten exceptional audio reports while using a VERY cheap computer microphone.
Operating an SDR transceiver requires the use of 2 different sound cards. I use one card that works as the digital signal processor for the radio and the other to drive the speaker on receive and mic for transmit. For the radio card, you want the best sound card you can get, with the lowest noise and highest sample rate. 92 khz sample rate cards are available with noise floors in excess of -100 dB, and they are common and inexpensive. I bought a Soundblaster Audigy card for this purpose, but with many soundblaster internal cards, there is some phase shifting in the card, and I couldnt get a good balance without setting the phase and amplitude all over the place. I've used an older USB card such as the Soundblaster Live external card and that works pretty well. The external cards apparently do not suffer from the phase shifting that the internal cards do.
With the bare transceiver with the fixed frequency settings, the only software that is useable with it is a special version of PowerSDR, called;PowerSDR-SR40 and is available at http://powersdr-sr40.sourceforge.net/. All other versions do not allow you to transmit if the fixed frequency is enabled. There is, however an add on module that allows USB control of the Si570 oscillator that allows continuous tuning, which I ordered but have not received yet.
I will write more stories on this radio, and will detail a little more precisely on setting up this radio for use. It is a fun little rig, and for roughly a $100 investment, you will have yourself a very capable little radio.
Thursday, November 12, 2009
New 2 Meter Radio
With all the driving I do with my job, I decided to purchase a new ham radio for my van. I drove up to Amateur Electronic Supply in Cleveland and picked up the new Yaesu FT-1900R. The one I wanted was discontinued, but this is looking more and more like it is a better radio.
One thing that has concerned me is that the new mobile 2 meter rigs run 50+ watts. This one is 55 watts, and the package is so tiny, I was afraid that there wouldnt be enough heat sink to dissipate the kind of heat that a 50 watt final would produce. Turns out the entire bottom of the radio is finned heat sink, and it runs really cool with no temperature rise. Could they be running a class E PA in their rigs now? It would make sense.
Now for the operation of the rig... For a new radio, it is relatively convenient. You do need to reference the user manual, however, as programming the radio involves a few keystrokes, especially when you need to use CTCSS to access a repeater. You can also name the channels so you dont have to remember the frequencies when you tune thru the memories.
Operating the radio is a breeze once its set up. Power level is changed between 4 steps using a front panel button, tuning can be direct entry via the DTMF microphone (standard equipment), or by turning the tuning knob. The receiver has a hot .2 microvolt sensitivity, and the transmit audio is nice and clean. I've made a few QSO's on the radio from the mobile, and I am very pleased with it.
I also started a yahoo group on this radio, and if you have one, you're welcome to join it. The url is at
http://groups.yahoo.com/group/ft-1900r/
One thing that has concerned me is that the new mobile 2 meter rigs run 50+ watts. This one is 55 watts, and the package is so tiny, I was afraid that there wouldnt be enough heat sink to dissipate the kind of heat that a 50 watt final would produce. Turns out the entire bottom of the radio is finned heat sink, and it runs really cool with no temperature rise. Could they be running a class E PA in their rigs now? It would make sense.
Now for the operation of the rig... For a new radio, it is relatively convenient. You do need to reference the user manual, however, as programming the radio involves a few keystrokes, especially when you need to use CTCSS to access a repeater. You can also name the channels so you dont have to remember the frequencies when you tune thru the memories.
Operating the radio is a breeze once its set up. Power level is changed between 4 steps using a front panel button, tuning can be direct entry via the DTMF microphone (standard equipment), or by turning the tuning knob. The receiver has a hot .2 microvolt sensitivity, and the transmit audio is nice and clean. I've made a few QSO's on the radio from the mobile, and I am very pleased with it.
I also started a yahoo group on this radio, and if you have one, you're welcome to join it. The url is at
http://groups.yahoo.com/group/ft-1900r/
Tuesday, September 22, 2009
E-H Antenna
Because of my limited space for antennas, I decided to do a little experimenting with an E-H Antenna. An E-H Antenna is a tiny HF and MW antenna. Originally designed for AM broadcast stations, these antennas supposedly operate with extremely high efficiency, but come in a very small package.
More information at http://www.eh-antenna.com/
I built one for the 30 meter band. The antenna is about 2 feet long, and have the antenna resonant close to the 30 meter band. According to my SWR meter, it currently runs about a 2:1 SWR on 10.139 MHz. I could get the swr down even lower by adjusting the matching coils. I did a rough tuning on mine, and got it close enough for now.
I've read mixed reports by hams who have built these antennas for themselves. Many say they dont work. Here is what I've found so far:
On receive, it seems to pick up a fair amount of noise, but that could be due to antenna placement. I dont have the antenna up very high, only about 10 feet.
On transmit, it appears to do fairly well, even at this height. Signal reports are about even using WSPR. I chose WSPR as an antenna testing mode because every station "advertises" their transmit power, so I can compare transmit vs receive efficiency easily. There is a difference, as my untuned 20 meter hamstick (going thru a tuner in the shack) consistently runs about 10 dB weaker on transmit than in my receiver.
Although this is not paint a complete picture, it does tell me that it works equally well, (or equally poor) between receive and transmit. When I am able to test the antenna when its up a bit higher, I'll be able to make better comparisons.
Watch for me on the 30 meter WSPR freq. I'll be beaconing using this antenna for awhile.
Sunday, September 20, 2009
10 GHz Mountaintop Operations
Saturday, Sept. 19 (2009) was the first time I have operated from a mountaintop on 10 GHz, and I'd like to share some observations from this particular trip. Because this was the first time I have operated from this location, Blue Knob, PA EN00rg, I'd like to tell you what I learned from this trip.
Mountaintop operations such as this tests the capability of your equipment beyond what I have experienced along the lake. Things such as receive sensitivity, pointing accuracy, etc are tested. On this trip, most of the signals are much weaker then what I experienced on Lake Erie.
One thing that was noticed readily on this trip, although our most experienced operator on site, KB8VAO said that this was a fluke, but the 2 meter band conditions were far better than the conditions on 10 GHz. Typically, signals on 10 GHz are much stronger than on 2 meters. Now I have noticed this up on the lake, but I figured this was caused by the duct over the lake being much smaller, and not able to support 2 meters. However, on the mountain, stations in New England were extremely strong on 2 meters, but almost imperceptible on 10 GHz. Many stations had to be worked on CW because the signals were so light. Most of the contacts were a struggle, especially the ones over 100 km away.
Although band conditions were such that there was a 2 meter opening, and 10 GHz seemed flat in comparison, I still managed to break my old personal distance record and worked Vermont which was just under 600 KM away. It was hit and miss for awhile, signal was quite weak, and had to be done on CW. I think next trip, I'm going to bring some form of headphones. I have found that headphones will give you about a 10 dB advantage, at least for me when working extremely weak CW.
The next week or 2, I'm going to compile an equipment checklist, I forgot to bring my code key, and had to borrow one to make the contact.
I worked about a dozen stations total from the mountain, ranging from 60 KM to 600 KM.
Tuesday, September 8, 2009
PowerSDR-IQ with the SoftRock v9.0 Lite+USB Xtall
I've been running the Softrock Xtall+Lite v9.0 with the individual band pass filter boards for several months before I broke down and purchased the Electronically Switched Bandpass Filter about a month ago. Ever since I got it, I had problems getting PowerSDR to switch the filter automatically. I know the filter works because it works fine using Winrad. Today, I got powersdr-iq working with the filter using a fancy little trick that I discovered.
The first thing I did was to uninstall powersdr-iq. I went into windows explorer and deleted what was left in the installed folder. I then went and reinstalled powersdr-iq.
Now here is where it gets tricky. If there is a .dll file in the installed directory called "ExtIO_PMSDR.dll", rename it to something like "EXTIO_PMSDR1.dll". Then go and download ExtIO_Si570.dll and save it in your powersdr-iq folder. Rename the file to "ExtIO_PMSDR.dll". Run Powersdr-iq. Go to setup > General > USB and UNCHECK BOTH boxes under AVR. Then go to the ExtIO tab, under General and check "PM-SDR Enable". Click the "Toolbox" button. You will get another box pop up. If you have Winrad installed and working with the dll for the Softrock, this box will look familiar. If you need help with this box, here's what you need to do with it.
Under "BPF", check "Enable". Normally the info in the band boxes would have for Band 0 1.8 to 4 mhz. I built my BPF so that band 0 is 50 - 54 MHz, so I changed those numbers. I also changed Band 1 to 3 to 7 MHz. You may not have to do this, but by experimenting with the cutoff freq's for MY individual filter, I found these numbers to work best.
I have posted to the usergroups regarding this problem, but it sure seemed that I was the only one that had this problem. I find that hard to believe, but now that I have this new dll installed, I can fully customize the filters, and they switch just like in winrad, probably because its the same software snippet that Winrad uses!
If you have noticed this problem too, give this fix a try. At the very worst, you might need to uninstall psdr and start over. This is all experimental software, and I'm sure that if youre using this stuff, you've probably uninstalled and reinstalled more than once anyway. Its worth a try. Let me know if it works for you too.
The first thing I did was to uninstall powersdr-iq. I went into windows explorer and deleted what was left in the installed folder. I then went and reinstalled powersdr-iq.
Now here is where it gets tricky. If there is a .dll file in the installed directory called "ExtIO_PMSDR.dll", rename it to something like "EXTIO_PMSDR1.dll". Then go and download ExtIO_Si570.dll and save it in your powersdr-iq folder. Rename the file to "ExtIO_PMSDR.dll". Run Powersdr-iq. Go to setup > General > USB and UNCHECK BOTH boxes under AVR. Then go to the ExtIO tab, under General and check "PM-SDR Enable". Click the "Toolbox" button. You will get another box pop up. If you have Winrad installed and working with the dll for the Softrock, this box will look familiar. If you need help with this box, here's what you need to do with it.
Under "BPF", check "Enable". Normally the info in the band boxes would have for Band 0 1.8 to 4 mhz. I built my BPF so that band 0 is 50 - 54 MHz, so I changed those numbers. I also changed Band 1 to 3 to 7 MHz. You may not have to do this, but by experimenting with the cutoff freq's for MY individual filter, I found these numbers to work best.
I have posted to the usergroups regarding this problem, but it sure seemed that I was the only one that had this problem. I find that hard to believe, but now that I have this new dll installed, I can fully customize the filters, and they switch just like in winrad, probably because its the same software snippet that Winrad uses!
If you have noticed this problem too, give this fix a try. At the very worst, you might need to uninstall psdr and start over. This is all experimental software, and I'm sure that if youre using this stuff, you've probably uninstalled and reinstalled more than once anyway. Its worth a try. Let me know if it works for you too.
Wednesday, September 2, 2009
1296 update
I had just finished rebuilding my 1296 rig and assembled the modules. I added a 3 pole bandpass filter between the transverter output and the 10 dB gain block that drives the 2 watt PA. When I initially tested, I wasnt getting any power out of the rig, so I proceeded to test for RF at each stage.
I was getting the usual milliwatt or two out of the transverter., but at the output of the filter, there was nothing. I retuned the filter for max output. I lost about 3 dB thru the filter.
After hooking up the low level amplifier, the measured output was about +8 dBm. A little lower than I expected, but it's enough to drive the 2 watt amplifier to a useable output level. A quick check at the 2 watt PA output indicated a healthy output. I then determined that I had the antenna relay hooked up backward, RX line going to the TX port, etc.
Once I got it all hooked up, there was an oscillation, which I cured by shielding the low level amplifier. The output is a little low, i think, but I still believe it is enough to so some good mountaintop work. I believe I can get a little more out of the transverter, however, so I'm sure I can get the power level up to where it should be. I guess the level to shoot for is +10 dBm out of the low level amplifier. So, it looks like I'm capable of getting on 1296 now.
I was getting the usual milliwatt or two out of the transverter., but at the output of the filter, there was nothing. I retuned the filter for max output. I lost about 3 dB thru the filter.
After hooking up the low level amplifier, the measured output was about +8 dBm. A little lower than I expected, but it's enough to drive the 2 watt amplifier to a useable output level. A quick check at the 2 watt PA output indicated a healthy output. I then determined that I had the antenna relay hooked up backward, RX line going to the TX port, etc.
Once I got it all hooked up, there was an oscillation, which I cured by shielding the low level amplifier. The output is a little low, i think, but I still believe it is enough to so some good mountaintop work. I believe I can get a little more out of the transverter, however, so I'm sure I can get the power level up to where it should be. I guess the level to shoot for is +10 dBm out of the low level amplifier. So, it looks like I'm capable of getting on 1296 now.
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