The UHF back2back link was moved from the QTH of ZS1DDK to Libertas on 4 November by ZS1DDK and ZS1TAF.
More maintenance was done today by ZS1VDV and ZS1TAF.
Today the equipment was moved on to racks in the cabinet and a link controller was installed. A powerpole distribution block was added and all power connections migrated to powerpoles.
Rack with radios and controller
This controller can now be used to link or unlink the back2back via DTMF codes.
8500 = Link
8504 = Unlink
On Wednesday 27 September at about 16:30, Paul ZS1V, Jan ZS1VDV and Wiaan ZS1WB met a representative of our Internet sponsor at the Helderberg high site to install one of the WCRWG Motorola SLR5500 DMR repeaters. The Helderberg high site is one of the easier ones to access due to its relatively low position at around 500m ASL and its proximity to the urban area of Somerset West.
Despite the relatively low elevation in comparison to other WCRWG high sites it is quite prominent above the 100m ASL average ground level. Good coverage is expected over most of the False Bay side of Cape Town, the Cape Flats and Northwards to Stellenbosch.
The team installed a Webb HD400 UHF dipole antenna and a short run of about 8m of EC4-50 Heliax. Shielded and UV resistant UTP cable was run from the repeater enclosure to a nearby enclosure for the DMR repeater’s Internet access. The SLR5500s configuration was updated to reflect the new IP environment before everything was tested and found to be satisfactory. Antenna SWR was measured at 1.2:1.
A first QSO on the new repeater was had on talkgroup 655 between Paul ZS1V and Koos ZS5KDK before the team wrapped up and left the site just before 19.00.
On Tuesday 25 July, Sean ZS1BSD and Paul ZS1V headed to Constantiaberg to attend to the 145.700 repeater which was transmitting, but not modulating. The weather was only a few degrees above freezing and it was raining with only 10m visibility at times. The lower part of the road was muddy an churned up by the heavy logging equipment in use in the area that is still clearing up the remains of the fire that devastated the area about 18 months prior.
Although the Motorola appeared to be working after a reset, it was removed for further testing and diagnosis and the PRF1050 backup repeater was installed in its stead. The PRF1050 has been fitted with a new CTCSS decoder, courtesy of Sean ZS1BSD. The required CTCSS deviation level is now more in line with typical commercial repeaters and not the very high levels required by the previous CTCSS decoder on the PRF1050.
Access to the site remains challenging. Specific access arrangements had to be made with the nature conservation officials with the help of Sentech.
ZS1BSD appreciating the fine conditions
Jan (ZS1VDV) and Rassie (ZS1YT) went to Hanskop to investigate the controller not responding to DTMF.
Started packing vehicle 06:30, left Stellenbosch 07:00.
Had to drive very slowly up as the road is in very bad condition and had the sun just over the horizon.
On site by 08:15. The temperature outside was 1.2 degrees, the wind was cutting through everything.
The problem with the controller was found to be interference on the 145.600 Repeater. The interference is not from our equipment but most likely from WISP equipment.
The 145.600 repeater’s SQL was closed to 1.1uV (about 4 times more that what it should be). This only helps about 80% of the time. The interference will need more work/investigation.
All SWR was checked. VHF repeater (1.1), UHF repeater (1.1), Jonaskop link (1.6).
CTCSS was added to the 434.650 repeater.
Home at Stellenbosch by 12:45.
Today Jan ZS1VDV and David ZS1DDK went to the site to service the power problem.
It was found that the DC power distribution box was faulty and replaced.
VHF repeater SWR was tested (1.2)
UHF repeater SWR was tested (1.4)
Backup battery voltage was measured (13.8V)
Jan, ZS1VDV went to Hawequa to investigate why the 650 VHF repeater was not working. The worst was suspected, that the mast did not survive the storms. Luckily this was not the case. The mast and building was in good condition.
It was found that the repeater was on, but as soon as it started to transmit it restarted. After long debugging, it was found that the repeater was not at fault but the dc power distribution box and power supply. The fault was corrosion on the conductors in the connectors (dust and soot blasted in by the storms, as well as intermittent power would have caused this), as well as crackling sound in the power supply.
The power supply will have to be replaced on a next visit and serviced.
It was great to see the water flowing off the mountain.
On Saturday 2017-05-20, Paul ZS1V and Rassie ZS1YT headed to Jonaskop to investigate a problem with crackly audio on the 145.675 Jonaskop repeater and to attend to some pre-winter preventative maintenance.
The weather was sunny, but cold, with a fresh cold breeze that could be felt as soon as one was a few meters up the tower. Most of the area to the South and East of Jonaskop was under thick cloud.
Overberg under a blanket
The SWR of the VHF antenna was found to be good. On previous visits water had been found in the connection between the feedline and the 4-stack antenna, despite there being a good water seal at that point. The phasing harness has a plastic tube section and extra precautions against moisture entering the system at that point were taken.
The link controller was also attended to, and audio crackle eliminated by re-seating some of the ICs.
An adjustment was made to the repeater configuration to make it go back to the desired setting after a power interruption.
The first digital repeater high site in the Western Cape was installed on Sunday.
ZS1VDV and ZS1DDK completed the main install on Sunday 19 March 2017.
UHF MMDVM Repeater and ICOM VHF DSTAR repeater and controller
The install on site started around 08:30. All equipment had to be carried a few 100m up the hill.
Uninstalled old equipment from rack.
Cleaned out all dead animals and dust.
Installed power supply unit.
Automatic transfer switch with low voltage dropout on battery side.
Power pole distribution block.
Installed networking router.
Did all network cabeling.
Installed MMDVM UHF repeater (DMR and DSTAR configured)
Installed ICOM ID RP2C controller and ID RP2000V repeater.
Installed VHF duplexer.
Made up coax fly leads.
Installed UHF HD 400 antenna.
ZS1VDV installing antennas
Did a final cleanup.
Returned home by 14:30
The morning started early and ended late. The wind on site provided an extra challenge, gusting at near gale speeds. Paul (ZS1V) started at 05:30 and met Jan (ZS1VDV) to load equipment in Stellenbosch at 05:50 before arriving on site at 06:20.
Battery was tested (12.6V).
Eskom power was down on the site, so no further debugging could be done.
Back in Stellenbosch 08:00
Left Stellenbosch 18:10.
On site 18:45.
Labelled all plugs.
Reprogrammed controller. (Flash memory in controller was corrupted after too many reboots.)
Tested everything and left site 19:45.
Back home 20:45.
David (ZS1DDK), Jan (ZS1VDV) went to do some maintenance on the Hermanus repeater.
With the last installation of the repeater it was found that the repeater rf sensitivity was not what was expected and needed to be corrected.
The weather was on and off with rain, the same as installation day, which did not make it fun.
Rain, not fun.
Started 06:30 in Bellville.
Pickup and pack equipment in Stellenbosch 07:15
Left Strand around 08:00
Arrived on site 09:15.
Debug repeater sensitivity. In the process to realign the front-end, it was found that one of the 4 notch filters tuning pots need to be replaced as it was damaged.
The spare repeater was installed, audio aligned and link controller reconfigured for new repeater.
Did some testing with Sam (ZS1OR). The spare repeater is better, but still some areas need to be looked at.
Left site around 11:30.
Extended the power supply power lead with 2m.
Got some “quick” lunch on the way back.
Unpacked at Stellenbosch 14:30.
Back in Bellville 15:00.