Brian, apology for the delay but hopefully this info will assist you -
Below is a summary of the HAMTV equipment and any relevant findings observed or experienced during set-up at VK4KHZ in Queensland Australia.
I have assembled two HAMTV stations at VK4KHZ, one is fixed and the other is a portable unit. I will start by providing a brief summary of each key component of each of the stations, the equipment in use and some of the learning's to date so that hopefully anyone intending to assemble a HAMTV ground station from scratch, utilising similar components, may avoid some costly and time consuming errors.
Sincere thanks to Jean Pierre F6DZP for assistance in providing the fantastic software and for assisting in initial fault finding.
Station 1 – Fixed Station.
Antenna: RFHAMDESIGN 1.2m prime focus mesh kit dish. This kit is easy to assemble providing you are patient with the assembly and are methodical with your assembly techniques. I did make a minor engineering change to the rim of the dish after placement of the mesh by riveting a section of 30 mm flat strap around the outside of the frame which makes the finish much neater, holds the mesh more securely in place and I believe improves the overall aesthetics of the design. This dish works very well and has provided consistent and reliable reception results.
Antenna Mount: The dish is mounted on a roof mounted ex pay-tv dish mount which is mounted just above the guttering line of the house roof. The vertical pole is 50mm diameter, approximately 1.0m in length and is braced with two 20mm stays. In all quite a rigid and serviceable mount.
Feed: The feed used is an RFHAMDESIGN helix feed designed specifically for HAMTV. This feed comes as a sealed PVC cylinder, however I did carefully remove the end cap by cutting it off with a hacksaw and replacing the original cap with a replacement push-on cap. I did this so that I could accurately measure the dish focal point distance as it was difficult to determine exactly where in the enclosure the helix started.
Cable: The feeder cable used is commercial grade quad shield 75 ohm coaxial cable with sealed crimp F type connectors fitted.
Converter: I have tried two (2) different brands of LNC in this installation. Initially I used the Spectra Developments SPDC 2400 LNC. This LNC works with HAMTV however at my location this unit seems to suffer slightly from an unknown interference source on 2395Mhz. It should be noted that the IF of the Spectra LNC is 1000Mhz for easy conversion. I am currently using the Kuhne MKU23TM in this installation as it seems to work much better for me and I do not get the interference issues previously noted.
Rotator & Controller: I am using the Yaesu G5500 (I could not find a supplier of SPID rotators in Australia otherwise I would have purchased one for comparison). I have three of the Yaesu (Kenpro) units and the standard controllers and they all behave with slight (and sometimes frustrating) differences. If you have one of the earlier models I would recommend that you perform a minor modification to the power supply unit in order to provide better voltage stability (addition of a capacitor), I have soldered a 1uf, 25v tantalum capacitor under the board between the voltage regulator’s output lead (+) and ground (-). I note that the latest model of the G5500 has this modification completed. The thing that I have learned about these rotators is that they can be used successfully for HAMTV use however some patience and persistence may be required during the initial calibration process to make sure that you get it right before installing. I have one unit which calibrated very easily using the process described in the Yaesu operations manual however the other two units took some time and patience to calibrate accurately. I would recommend that you calibrate the rotators on the ground rather than mount them on your mast/tower and then try and do the calibration from the roof or ground. The dish mount I use is a custom built unit C/W adjustable sliding counterweight arms which are adjusted to find the balance point of the dish when mounted on the rotator – I consider this to be critical as using this method can greatly reduce the amount of “play” between the rotor gears during high elevation passes. The counterweights which I used are weightlifting barbells as they are heavy, cheap and easily available.
Antenna Tracker: I currently use an LVB Tracker (available from AMSAT) at my fixed station, however before calibrating the LVB Tracker I did calibrate the rotator controller using my Yaesu GS232B antenna tracker – (I simply found that by using the GS-232 to calibrate the rotator controllers before installation was the easiest approach) and then calibrate the LVB tracker to match the rotator.
Computer: Dell 990 Desktop, 3.1Ghz, 8 Gb, 250 GB, Windows 7 32 Bit system dedicated for HAMTV use
Satellite Receiver: TechnoTrend TT S2-1600 PCI Card. It is worth noting that the initial card which I purchased and installed into the PC, I spent literally weeks trying to get it to work, and without success. It was only after I contacted Jean-Pierre F6DZP (just in case I was doing something wrong with the software) and a series of tests were performed in which we determined that the receiver card was in fact faulty. I purchased a replacement card and it worked first up. I must say that without Jean-Pierre’s support and Martin (VK6MJ) persistence in convincing me not to give up I would most likely have shelved the project.
Tracking Software: I use SatPC32 on all three (3) of my tracking stations for no other reason than the fact that I like it, and it has never let me down. The set up process is pretty much self-explanatory however if anyone is experiencing difficulty please feel free to contact me and I should be able to assist, having tried most of the settings.
https://www.youtube.com/watch?v=rZJRH17x0FI
Station 2 – Portable Station
Antenna: Initially a 1.6m steel petal dish however I am now experimenting with an Ex commercial 1.6m solid aluminium prime focus dish with a custom built light weight mount.
https://www.youtube.com/watch?v=lwKrLAx5FNg
Antenna Mount: 1.2m section of aluminium lighting tower mounted on an aluminium tilt over base with hinge and fitted with heavy duty locking trolley wheels. This unit fits easily into the tray of my vehicle (Toyota Hilux).
Feed: Home-made 2.4G patch feed made from 100mm sewer pipe (un-used!) aluminium sheet and single sided PCB board.
Cable: The feeder cable used is commercial grade quad shield 75 ohm coaxial cable with sealed crimp F type connectors fitted
Converter: Currently using a Kuhne MKU23 (not the TM model) built into a home-made weatherproof enclosure. This particular model comes without a weatherproof enclosure.
Rotator & Controller: Yaesu G5500 with custom built mounting frame for the dish C/W adjustable counterweight arms. Counterweights are weightlifting barbells and the counterweight assists in reducing backlash from rotator as gears mesh particularly at high elevation.
Antenna tracker: Yaesu GS-232B rotator controller
Computer: Dell 990, 3.4Ghz, 500Gb, Windows 64 Bit system
Satellite Receiver: TechnoTrend TT S2-3200 PCI Card. (The S2-1600 is no longer available)
Alignment: Alignment is completed using a spirit level and a Garmin GPS each time the system is moved. To date it has proved to be a relatively simple process.
Other Notes worth mentioning:
The mounting clamps on the elevation rotator should be replaced with better quality heavy duty clamps (available at local TV antenna retailer) the mounts that come with the rotator are light duty.
The LNC should be mounted as close as practicable to the input of the dish feed.
If the length of control cable feeding the AZ/EL rotators is changed it would be wise to recalibrate the rotators as I changed from 15m control cables to 25m control cables and found that this change caused a minor discrepancy in the accuracy of the rotators.
Getting the focal length correct (within 5 mm) can and does make a difference. My view is the RFHAMDESIGN helix feed should not have the end cap glued in place.
Try and mount your dish as clear as possible from any obscuration – especially trees and foliage.
The Kuhne MKU23TM is NOT waterproof, only weatherproof. Be aware of this especially when it is raining and the dish is operated in flip mode.