Category Archives: Maintenance

Maintenance Hanskop 20170722

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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.

Maintenance Hawequa 20170625

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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)

Maintenance Hawequa 20170617

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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.

Jonaskop maintenance

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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.

Repeater Installation Bottelary 20170319

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Panoramic View

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.

Equipment Rack

Made up coax fly leads.
Installed UHF HD 400 antenna.

ZS1VDV installing antennas

Did a final cleanup.

Returned home by 14:30

Maintenance Hawequa 20170221

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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.)

Sunset

Tested everything and left site 19:45.
Back home 20:45.

Hermanus maintenance 20170212

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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

Equipment packed

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.

Hawequa maintenance 20170128

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Paul ZS1V went to the Hawequa 145.650 repeater site on Saturday morning 28 January, to diagnose a fault that was causing the link to operate in one direction only.

The effects of the recent fire were evident.  The veld had burned on both sides of the access road and to within 1m of our building that houses the repeater.  Fortunately, both our building, tower and the area in between where the coaxial cables are in the cable tray, were spared.

The destruction was quite wide-spread.  The poles supporting the electrical feed to the site have been burned and will likely need to be replaced.  For now, the power is still on.

Some diagnostics on the link controller were done and some settings adjusted.  The link is functioning correctly again, albeit still with slightly misaligned audio.  This will remain the case until firmware fix is provided by the link controller suppliers, enabling the return to the required configuration.

Link Installation Hermanus 20170115

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ZS1TAF left home at 07:00. ZS1DDK, ZS1VDV, ZS1V and ZS1OR were collected and all the equipment was loaded in 2 vehicles.

The team arrived on site at about 09:45.

View

Unpacking

The weather was windy, misty and there was some rain to complicate matters. The team all got stuck in and many of the tasks were executed in parallel.

Raining, ZS1TAF sealing new UHF antenna, ZS1V keeping rain off ZS1VDV tuning the duplexer

The first step was to confirm the correct SWR on the current VHF installation.  This was found to be an acceptable 1.2:1.

The previous repeater was removed and the hut cleaned out.  A Webb HD400 UHF dipole, fed by half inch Heliax and an LMR400 patch lead, was installed with lightning protection, for the link to Hanskop some 40km away.

ZS1TAF sealing the UHF antenna with ZS1OR

The duplexer was retuned which improved the insertion loss from 3 dB to 1.5 dB, and the rejection from 65 dB to 82 dB).

145.725 duplexer results after tuning by ZS1VDV

The UHF power output was measured at 2W and SWR on the antenna system after installation at 1.1:1.

As with many of the WCRWG repeater installations, the new link controller installation includes inside and outside temperature sensors as well as a DC voltmeter that can be queried by sending DTMF codes.

The repeater power output was measured at 10w after the duplexer.  Due to local noise levels, the squelch of the repeater had to be tightened somewhat.

The team left the site at about 13:00 and everybody was back home with the vehicles unloaded by around 16:00.

Maintenance Hanskop 20161030

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David (ZS1DDK), Andre (ZS1AN) and Jan (ZS1VDV) did maintenance on Hanskop.

Summary:
Removed UPS, replaced with battery and charger
Changed UHF repeater frequency (434.650 output/ 433.050 input)

Log:

Left Bellville 06:45.
Packed all equipment in Stellenbosch (07:45) (4 ammo crates, 2 x 15L storage boxes, 1 tool box(very heavy), Pelican case, comms test set, table and chair). (Takes about 1.5 hour to prep all equipment).
Collected battery and low drop out switch in Somerset West from ZS1V (08:00).
Collected key from ZS1YT (08:15).
Arrived on site at around 09:05. (15 degrees Celsius)

Unpacking

Unpacking

Removed faulty UPS (Battery banks is dead).
Installed new Victron Energy Charger.
Collect more equipment at N2 (Thank you Melissa (ZS1MEL) for driving from Stellenbosch).
Installed battery (donated by ZS1V).

Backup Battery

Backup Battery

Changed power wiring for new configuration.
Retuned UHF duplexer for new frequencies (434.650 output / 433.050 input).

Retuning Duplexer

Retuning Duplexer

Duplexer

Duplexer Results

Made changes to repeater configs.
Tested UHF repeater (1.5 SWR and 0.56uV sql)
Made changes to link controller.
Left site 14:23. (4 degrees Celsius)
Drop key at ZS1YT 15:15.
Unpack equipment in Stellenbosch 15:50.
Home in Bellville 16:30.