PEARS REPEATER MAINTENANCE LOG: 1975 - 1999

REPEATER WORK (current)

REPEATER WORK (2015)

REPEATER WORK (2014)

REPEATER WORK (2013)

REPEATER WORK (2012)

REPEATER WORK (2011)

REPEATER WORK (2010)

REPEATER WORK (2000 - 2010)

(this page)

 


A record of trips undertaken to various repeater sites by PEARS members or helpers (reverse time order)

DATE SITE VISITED PERSON/S ACTION
22 November 1999 Governorskop ZS2AAW Maintenace checks

UHF Link to Cradock
TX -4.5kHz
TX Dev 3.2kHz
TX power 3W
VSWR 1.4:1
RX discr -54mV
RX level 1375mV

UHF Link to EL:
TX -1.5kHz
TX Dev 2.9kHz
TX Power 2.5W
VSWR 2.5:1
RX discr +51.4mV

RX level 1210mV

UHF Link to PE:
TX -1kHz
TX Dev 3.8kHz
TX Power 3W
VSWR 1.5:1
RX discr -4.7mV (good)
RX level 1120mV (OK)

VHF Repeater:
TX -300Hz
TX Dev 3.5kHz
TX Power 6W out of duplexer
VSWR 1.9:1 (co-linear?)
RX discr 4.3mV (good)
RX level 1160mV
SQ level 0.5uV thru filters (OK)

6 August 1999 Garden Route club ZS2AAW Donations made to the Garden Route club as follows:

Danabaai:
UHF Link to George serial no:  C41641
Control card DTM code 6004
VHF Repeater serial no:  K43753
UHF Link to Stilbaai serial no:  C41899

Stilbaai:
UHF Duplex link serial no:  C41634
VHF Repeater and a spare was supplied by them

25-28 July 1999 Lady's Slipper ZS2AAW Bush fire!
Brings the power line down on Sunday ~ 14h00
Visit the site to inspect damage on Monday am
Power only expected back on Wed, so switched off the DC loads (batt @ only 20V)
Not much fire damage - maybe just the RG213 feeders

Wednesday
power is restored
Checked heliax feeders -all OK
VHF Repeater only has about 5W output

HF 12V PSU faulty - blown DC fuse
Caused by crowbar cct operating, possibly due to carbon conduction between -ve unregulated DC on the diode, and the casing

Packet BBS PC PSU no good - brough down for repair

  Cradock ZS2JM, ZS2AAW VHF Repeater:
Had no TX output - removed for repair
Found blown finals
Repalced PA twice until a clean output could be obtained

Refilled batteries - VERY low

Changed top UHF co-linear, but had bad VSWR 2.7:1
Found antenna to be faulty & brought back for repair
Re-fitted VHF repeater - 10W output out of filter
Re-aligned filters (Swapped VHF RX around)

Reset charger from 28.8 to 28V float (under no load)

All antenna checked OK on VSWR
Feedlkines were OK

Left the link running on the 8el yagi (packet link) to GHT

27 February 1999 Cradock ZS2AAW VSWR measurements:
650 TX 1.4:1 (had water in top connector)
650 RX 1:1  Good
UHF Yagi  1:1 Good
VHF Packet  1:1  Good

Set VHF packet o/p to 5W

1999

11 December 1998 Buffelsnek ZS2DD, ZS2AE, ZS2AAW, ZS2AZR Site is stand-alone due to faults on the links

Found the simplex link to Kareedouw would key itself when receiving!
likewise on the George 1/2 duplex link
Problem found on the 434.825 link control card - COCKROACH!
Deposit on the tracks causing leakage
Cleaned up and all is OK

Fitted 10n caps on all contrll cards to power up in the combined/connected state
Fitted delay card in the 1/2 duplex link to George to stop the RX blip from the far side.  Works OK
Full maintenance run - netted all frequencies, deviations, aligned filters.  
All VSWR's are good

Did modification to kill the RX of the VHF repeater if the links key its TX.
Works OK, but will cause problems if the repeater is disconnected, as the link traffic will still kill the RX!
Needs to be sorted out on the next visit

9 December Governorskop ZS2DD, ZS2AE, ZS2AAW, ZR2JH Replaced co-linear AGAIN - back to the original one, but it has been extensively cleaned up, paying special attention to the tuning ring contact area against the aluminium pipe section.  There was bad corrosion there before.
VSWR bad at 1.7:1
Maybe need to tune it in position?

Replaced UHF link yagi to EL
Feeder is waterlogged
VSWR into dummy load on top is >3:1 !!!
Could not improve this after drying out the connectors
Need to replace the feeder

Fitted RX Osc delaying cct to link from Cradock, but still get a blip on the RX when keying down the TX to Cradock (far side is duplex UHF link)

5 December 1998 Cradock ZS2DD, ZS2AE, ZS2AAW, ZR2JH, ZR2SC Complete installation:
Accomodation in old Eskom site battery room
Install link, repeater & packet antennae
Install radio equipment
Batteries ex SAPS/Knysna solar site re-used here

Top VHF RX antenna heliax connector possibly loose
Top UHF antenna or feeder suspect - poor VSWR

Can't get a good signal on the top UHF antenna from GHT
So are using the lower 8 el Yagi for the link - good signal

November 1998 Lady's Slipper   Power meter re-instated by PE Munic

6m Link antenna fitted and 6m unit installed
left disconnected due to 6m interference

Batteries topped up

Old 50mm steel pipe cut down and removed, with its stay wires etc
Cleaned up around the shack

October 1998 Governorskop ZR2JH Repeater removed from GHT and brought back to PE

Found an intermittent problem on the control card causing the noise - a non-soldered resistor!
Cured the noisy squelch tail problem, and the noise on TX too.

Refitted to GHT, but antenna crackle is still there

8 October 1998 Governorskop ZS2AAW Bypassed all multi-core connector pins with 10n caps
Added ferrite core
Cured the noisy quelch tail problem, but there is still crackle on the incoming signals, as if it is a bad antenna bending in the wind...

To prove the antenna, will fit a 1/2wave end-fed to compare to.

24 October
Repeater is bad now - only noise on transmission
No DTMF control of the repeater or link to EL

September 1998 Governorskop ZS2AE, ZS2AAW Change co-linear
Fitted ex Uitenhage refurbished one
VSWR not great at 1.5:1
Crackle on squelch tail is bad, but goes if repeater is disconnected from links
Fitted DTMF control card on repeater - 7500 * / #
29 August 1998 Governorskop ZS2DD, ZS2AE, ZS2AAW Investigate crackle on the VHF repeater
Seems to be inside the co-linear
Feeder is OK
Co-linear VSWR is 1.5:1

434.850MHz UHF Link to EL:
VSWR 1.5:1
TX power 7W
Re-netted the frequencies, both TX & RX

431.150MHz UHF Link to Cradock:
VSWR 1.3:1
TX power 3W
Re-netted frequencies (5kHz low on TX, RX was -100mV on discriminator)

431.100MHz UHF Link to Slipper:
VSWR 1.3:1
TX power 3W
TX netted frequency

VHF Repeater:
TX o/p after duplexer 6W
Netted frequency on RX only
Re-adjusted packet filter & duplexer
Antenna is a problem

  Mount Rd ZS2AE, ZS2AAW, ZR2SC New repeater and link commissioned:
Fitted Storno repeater - replaced old Philips/PYE unit
Mounted cavity filter notch on TX line
Checked antennae - RX VSWR not good, TX is fine
Fitted 2ch UHF Link, with 3el Yagi towards Slipper
65011 or 65012 to link to Slipper or Town UHF
Repeater PSU has some ripple on it - needs to be upgraded
Ready for the VW Rally...
11 June 1998 Lady's Slipper ZS2AAW Slipper BBS:
Found the UHF backbone TX to be 3.5kHz low
RX also -51mV on discriminator
Reset the trimmers, and hopefully all is OK
29 May 1998 Uitenhage ZS2AAW New repeater commissioned:
Fitted repeater, filters, mains PSU
Fitted UHF link towards Slipper/Town UHF
Two channel control card in link - 67511 or 67512
Left it coupled to 650 UHF for running-in
22 May 1998 Lady's Slipper ZS2AAW Interference:
Paging intermods on 700 squelch tail or when incoming UHF signals
Found 158.350MHz and 158.950 and 145.700 mixing together
950 is a pager firm - rough signal @ squeal on carrier
350 is kerchunked all the time - must be a repeater of sorts
Jim, ZR2JRF telephoned a pager company and they said they would check it out
fault seems to have cleared!

Sunday - still no sign of interference...

Monday - back in full force

Reported to SATRA ~ 28/5/1998

Seems clear after returning from Jhb 11/6/1998

22 March 1998 Lady's Slipper ZS2AAW UHF Link:
Off frequency by 25kHz!!!
Need the repeater for intechnet tonight
Remove 33pF padding & re-fit 5p6 cap
Trimmed out fine
TX o/p 5W
TX & RX Frequencies netted

VHF Repeater:
Check VHF Repeater filtering & adjust
Trim TX o/p matching - lifts o/p from <2W to > 7W
Set o/p to 6W after filters
Check netting - OK

VHF Packet:
Check packet VHF Filtering & adjust
Also check TX matching & adjust
Set o/p power to 6W too

20 February 1998 Lady's Slipper ZS2AAW Lightning damage:
Blown LM324's and TL074's
Caused link to key up permanently
Also kept VHF packet RX open, so not useable
Also keyed up backbone

Visited again on Monday 23/2 to re-instate packet network

Many trips to finally sort out HF auto-patch
Final cure was to capacitor bypass multiplug and ferrite core on the multicore cable from this plug towards control card

1998

? Governorskop ZR2SC, ZS2AE, ZS2AAW Tower repair day
Remove 3x broken sections
Cut & fit new thick-wall 25mm dia aluminium tube
Fit original co-linear, which has been checked over and re-assembled by ZS2AE, thanks Dad!
9 December 1997 Governorskop ZR2JH, ZS2AE, ZS2AAW Bad VSWR on Repeater Co-linear - 3:1 !!!

Found heliax is OK, but PL259 connector is corroded on centre pin
Co-linear centre pin socket is also dirty & flared
Clean up and re-tension fingers

Cut off & re-make heliax connector to N-type female
Make flexible tailpiece into co-linear
VSWR now good, and stable

Tower is in poor condition:
3 cross-pieces are broken and need replacement
Possibly causes crackling too
Topmost bolt into angle iron is loose too
Need to replace with stainless one

? Lady's Slipper ZS2AAW, ZR2SC Fit UHF Bosch rig for 9600bd packet
Refit HF Rig with new channels
Fit shelf for TNC's and 12V PSU
Fit Relay control for reboot of PC and TNC's via mains relay

Configure 9600 port and check it out - all OK
Also HF port - all OK
Load procomm onto PC for TNC commands
BBS PC won't reboot:
Remove PC & check motherboard - clean up & refit
Change screen - old one has PSU problems (blown)

HF Rig has high VSWR > 2:1 and locked up the whole system on Sunday bulletin 7/12/1997

Re-netted 7066kHz (was 800Hz high)
Others all OK

HF packet o/p set to 40W in KAM
Fit 50k pot in place of R25
Adjust 9600 deviation to 3kHz
Netted 434.875MHz frequency
Nett UHF Link TX (was -3kHz), UHF Link RX (-2kHz) on 438.700 link
Output still 5W
VSWR <1.5:1 on diplole

20 November Buffelsnek ZS2AE, ZS2AZR, ZS2AAW, ZR2VM Change Batteries
Change frequency to 145.675MHz
Add TX pass cavity filter on 145.675 line
Add control board into repeater - 6750 * / #

Leave keyed up - no intermod interference crops up

VSWR on all four antennae is good

Link to George: 3W
Link to Kareedouw: 1W
VHF TX out of all filters: 4.5W

Links were re-netted
Removed oven supply on UHF RX from George (forgot last time)

Codes changed to 
PE link - 675A
George link - 675B
Repeater - 6750

17 October 1997 Lady's Slipper ZS2AAW Visit to remove HF rig to install new crystals
The following frequencies are now fitted and netted:
  1. 3.640
  2. 7.098
  3. 7.066
  4. 7.082
  5. 7.070
  6. 7.0397
  7. 10.1487
  8. 14.1047
  9.  3.590
  10.  
  11. 3.605

Mods done to use HF packet when in standby mode from auto-patch relays

15 October Governorskop ZS2AAW ROSE Switch:
PSU blown - burnt out
Removed to rebuild
New bridge rectifier required
15 October Uitenhage ZS2CB, ZS2ML, ZS2AE, Gordon Harris Site visit to assess situation

Tower height: 30m
Pipe feed to tower: 7m
Entrance to rigs: 6m

12 October 1997 Governorskop ZS2DD, ZS2AE, ZS2AAW, ZS2NV & XYL Change co-linear TX/RX antenna to remove "wind crackle"

Change VHF packlet end-fed to a folded dipole - to improve coverage
Change EPROMS in both MFJ's in case of programming problems (SAME Checksums though)

VSWR on VHF packet fdr: 1.5:1 into dummy load up top, 1.8:1 into folded dipole
VSWR on VHF co-linear < 1.2:1 - OK

Earth Storno's together with 2.5mm green wire - must re-do this though
Some crackle removed on squelch tail thanks to earthing
Gets better if either PE or EL links are unplugged

De-rust container rim (external)

At home later:
Downloaded TBL files to ROSE switch
but have no comms on the UHF backbone to Slipper (no TX or RX)
Nothing in UHF heard list either

25 September 1997 Lady's Slipper Investigate interference report - 146.175MHz Comspec - Johan Basson
We are desensing them
No problems found

Remove 51.400 set

Fit ex-GHT batteries & take others home for re-work

Panel side & remove mains sockets

30 August 1997 Governorskop ZS2PP, ZS2QN, ZS2DD, ZS2AE, ZS2AAW, ZR2SC Re-install ROSE switch at repeater site
Fit 8el UHF Yagi towards Slipper at top of mast, plus heliax
Fit 2nd 8 el UHF Yagi in middle of mast towards Slipper, with heliax - to be voice link to PE
Turned old 8el UHF Yagi antenna from PE towards Cradock for voice link
Run new heliax for lower VHF end-fed antenna
Used old VHF TX heliax for UHF Link to Cradock

Fitted ZS2WG's duplexer and one aluminium filter in TX line to notch out 144.675MHz packet
From TX thru aluminium filter had 15W o/p
After duplexer had 5W o/p
Duplex test was OK - Squelch opens at 0.5uV, quite cleanly

One aluminium filter in Packet VHF line to notch out 145.150 and 145.750 together

Check VSWR on UHF links - EL & Cradock are both bad, PE is OK

Top up all batteries - were on MIN mark

PS:
no packet VHF transmission back in PE, must be a problem...?

9 August 1997 Kareedouw ZS2AAW TX towards Slipper noted to be very low.  Have had poor link transmissions from Knysna to PE for a week or two

UHF Link to Slipper
Found no TX power at all on 431.100 unit
Replaced PA module, returned and got 1.5W, reset to 1W and refitted
Netted TX Frequency to 431.100MHz, was 1kHz low
All OK

Has been a bush fire at some stage on the mountain

434.875 TX fine @ 1W, ~250kHz low

4 August 1997 Lady's Slipper ZS2AAW ZS0NTP BBS:
No UHF Packet backbone comms since Saturday am.
Was a power interruption at that time - possibly a transient?
Found KAM locked up - no reponse to PC or on air
UHF rept still worked OK, but had continuous tone on any retransmission (from KAM)

Powered off-on, then OK

31 July 1997 Fedlife Building ZS2WG, ZS2DD 438.650 UHF Repeater:
Removed repeater - no TX power output
Found loose mounting screw on PA board - thus no supply to middle RF transistors
Could not line up L6 properly on exciter board - may be a problem?
4 July 1997 Longmore ZS2AE, ZS2U, ZS2AAW & young family Temporary Rally Repeater
Installed the repeater and solar panels + link at Longmore Forest repeater site - 3000' asl
Ready for rally check run on the Saturday

VHF TX Power 6W
VSWR good

Had problems with DC connectors on the solar regulators and a blown fuse.
All working OK

PS:
worked f/b for the rally
removed on Saturday 19th July

? Lady's Slipper ZS2AAW HF Rig:
Re-net the HF channels, some as far off as 350Hz

Clean out rat droppings etc

UHF 9600 port antenna and feeder is fitted & waiting for 9k6 rig installation

PS:
HF was again causing distortion on the Sunday Bulletin, so there is still an antenna problem...

15 June 1997 Buffelsnek ZS2AE, ZS2AAW, ZS1J, ZS2AZR, ZR2SC Change repeater to 145.750 to circumvent intermod problems on site
Re-align filters
Check all VSWR's - OK
Re-align repeater TX - spurious and not stable on new frequency
Finished up with 7.5W max, backed off to 6W out of filter

Exchanged UHF Link unit to Geroge to clean up distortion problems on this link
New unit has new TX crystal fitted

Netted other UHF Link - a few kHz off
TX Power 1W to Kareedouw

Roger & Shawn changed TX antenna to a folded dipole

Checked solar regulator: Drops off load @ 21V, re-connects @ 25V - OK
Charged batteries, all checked OK on SG hydro
Found bad fuse connection which possible caused low volts drop-off of the system. Sprayed fse holders with Q20

Stayed overnight at ZS2ZAR

16 June 1997:
ZS2AZR, ZS1J returned to site to inspect DC and found one bad cell in the bank, so need to replace the batteries sooner or later

Also reported that the link distortion towards George still comes up on occasions

5 June 1997 Lady's Slipper ZS2AAW, ZR2JH Packet Backbone:
Re-adjust UHF Backbone TX Frequency on BBS - was 5kHz high
RX also 2-3 kHz off, adjusted
Governorskop Digipeater was u/s because of this
Forwarding to Jim also had been a problem

Found HF antenna legs loose - rusted through.  Need to replace these

1997

9 December 1996 Lady's Slipper ZS2AAW FBB software locked up two days in succession
thought to be a problem with GPSERV
Will change some file configs & try again
? Governorskop ZS2AE, ZS2AAW, many helpers Relocate all equipment from old telephone booth to the new Porta-Camp on site
Move AC power cable
Fit new battery bank 24V 40Ah set
Recalibrate charger float voltage to suit

No Checks or changes done to the actual equipment

ZS2PP, ZS2EN, ZS2QN later removed the remains of the telephone booth and all other scrap items from site - thanks guys!

3 December 1996 Governorskop ZS2AE, ZS2PP, ZS2EN, ZS2DD, ZR2ARB, ZS2UN, ZS2AZ, ZS2VM, ZS2AAW Delivery of Portacamp "container" ex Eskom Alexandria Repeater site

Cleared, levelled and fence removed from around old telephone booth
Concrete slabs set and container placed on old fence poles
Door requires attention

Cost R399.00 for transport

ZS2ND to deliver newer 45Ah batteries next week.
Equipment to be re-located at a later date
Batteries topped/filled - were completely empty again

BEFORE:

DURING:

AFTER:

 

18 November 1996 Lady's Slipper ZS2AAW Early morning visit - site went dead on Sunday am before builletin time.  Batteries ran flat
Found charger DC fuse faulty, not blown
10A foil type, where the foil had n/c to the end cap
Soldered 3x rip cord strands over the fuse (!!!)

Changed parameters of UHF backbone port:
FRACK to 5s (was 2.5)
PACLEN to 180 (was 230)
MAXFRAME to 2 (was 3)
PERSIST to 80 (was 130)

Need to get a stock of fuses...

4 November 1996 ZS2LR ZS2AAW Deliver UHF Bosch rig on 438.275MHz UHF Backbone) to Jim for forwarding to Slipper
3 November 1996 Governorskop ZS2AAW, ZS2AE, ZR2EY, ZS2PP, ZS2EN Re-installed the ROSE switch at Ian Alan's farm
Operates f/b into Slipper
No problems
25 October 1996 Lady's Slipper ZS2AAW Found blown AC fuse on charger - need to get a stock of 3A slow blow fuses for AC

Re-fitted mains fail alarm after repairs were done on it to ensure the alarm is reported every ~20 min

Organised 45Ah Plante cells x13 for Slipper DC refurbishment sometime

23 October 1996 Lady's Slipper ZS2AAW Found the site to have no mains supply
Battery volts at 20V
Phoned PEM to report

Site visited again later that day:
Found HF Rig DC fuse blown
Repaired and all is OK again

PS:
Failed on 24/10 again - sounds like no mains supply again
All repeater s eventually died by evening 24/10

3 October 1996 Governorskop ZS2AAW Remove ROSE switch and take to PE
UHF Bosch to be replaced with high power version
EPROM to be updated to do UI Frames
24 September 1996 Governorskop ZS2AAW Re-install ROSE switch/Digi at Governorskop
UHF signals poor
23 September 1996 Lady's Slipper ZS2AAW Install BBS on the mountain
24 August 1996 Lady's Slipper ZS2AAW Re-install HF Rig with mods etc

Repair HF dipole antenna - one leg broken off at lug on perspex top insulator feed point
Fit lengths of flexible wire to connect to stainless steel dipole elements to perspex feedpoint to prevent same fatigue happening again
VSWR back to 1.2:1 - OK
Check frequency netting - ch2, 3, 4 are OK, ch1 is 1kHz high!

Modify DTMF Repeater control card with diode as above to inhibit reply tone breakthrough

Swapped control cards around so now disconnect card is in UHF link, and straight card is in VHF Repeater
Checked for HF distortion - none apparent
Earthing must be helping this problem

Reconnect mains-fail alarm and test - OK

Reconnect 6m link with squelch tight

? Lady's Slipper ZS2AAW HF Rig has gone high VSWR again
Removed rig to modify ch3 and ch4 to remain open-squelched for HQ relaying on Sundays

Also added diode pin 7 (LM555) to pin 12 (U11) to inhibit tone oscillator when not required, so that no tone break-through occurs

23 July 1996 Lady's Slipper ZS2AAW Experience intermods onto Eskom ch11 input
Have to remove units until better filtering can be installed

Do much-needed battery maintenance
Clean posts, wash batteries
Re-assemble battery bank

17 July 1996 Lady's Slipper ZS2AAW Installed 2 more Storno's for packet corssband
5 el UHF Yagi towards town, plus folded dipole on VHF port
2 heliaxes run
2 aluminium filters, plus TX cavity thru filter on 144.600MHz

Remove 6m link due to interference

20 June 1996 at home ZS2AAW Fetched BBS from ZS2WG before he left for overseas

Investigate KAM's reluctance to copy signals on 144.675MHz
Found eventually that the equalisation jumper on VHF RX was off - reset it to default and all came right
Lined up 2 Bosch UHF rigs on 438.600MHz (new backbone) and 434.875MHz (new 9k6 port) for packet use, plus 2 Storno's on 144.600MHz (new PE VHF port) and 438.600MHz (Slipper Backbone port)

Received new KPC9612 and interfaced it to the two Bosch's
Set the two Storno's up to crossband from KPC ionto 144.600MHz at ZS2AE's QTH
Run BBS like this, forwarding on '600

10 June 1996 Lady's Slipper ZS2AAW Re-installed HF Rig with 
ch3 = 7066kHz
ch4 = 7082kHz
7 June 1996 Lady's Slipper ZS2AAW Removed HF Rig from site to install 2 more channels for auto HQ bulletin relays
23 May 1996 Governorskop ZS2AAW, ZR2JH Found VHF TX to be spurious, causing howling lock-up whenever temperature was right
Retuned PA stage o/p through filter into IFR, and all cleaned up OK
Power set back to 8W out of filter (max 12W)
Power was <3W when first tested.
Re-connected links and put network back to normal

PS:
Anton vd Merwe (SATRA) reported that the former Ciskei Water Board has changed out the Salisbury Plain radio that was causing telemetry interference via Governorskop - thanks!

14 May 1996 Kareedouw ZS2AAW, ZS2AE Brief trip to fit power-off relay, controlled by saltmine telemetry system, so that the links can be switched off completely for interference tracing

Also tracked 145.100MHz bursty interference and also continuous carrier interference.  Latter is EMCOM base station at Humansdorp RSC workshop (& vehicles) - Local Oscillators are on 145.100MHz

Checked J-Bay alarm companies with IFR spectrum analyser, no problems noted.
Burst type interference seems stronger at Humansdorp, not J-Bay

3 May 1996 Kareedouw ZS2AAW Replace antenna change-over relay in link to Slipper
Re-tune TX of this link and power is up to >2W

Check both antennas, VSWR is <1.4:1 so both OK still
Netted frequencies of both TX's

Trying to trace howling type lock-up interference.  Thought it was originating at Kareedouw, but all looks clean here

29 April 1996 Lady's Slipper ZS2AAW, ZS2AE Bulletin yesterday was chaos - HF TX distorted everything, and could not disconnect via DTMF...

Found a loose connection on HF dipole which caused >3:1 VSWR!  
Tightened and glued the bolts
VSWR down to 1.2:1 again
But still had distortion problems
Installed earthing busbar and strapped VHF & UHF Storno's to it, as well as DC to DB +ve, and HF Rig, mains earth
This cured the HF distortion probelms (for now)

Tracing VHF (145.100MHz) interference with spectrum analyser - could not discern which transmission is spurious.  Seems like a distant/weak signal, on-channel.  Could not determine from which direction either

Re-netted HF TX back onto 7098 & 3640 kHz

8 March 1996 Lady's Slipper ZS2AAW Refit bypassed original control card to VHF Repeater
Still have distorted audio on VHF TX with HF enabled

Had to put DTMF card into VHF Repeater & mains fail card into link to cure the distortion problem.  
So leave mains fail alarm disconnected

Need to come back to analyse problem with HF transmissions

Noticed a heterodyne on VHF TX when keyed...?

4 March 1996 Lady's Slipper ZS2AAW Simple control card with mains fail alarm fitted to repeater - fixes distorted audio & low level on VHF TX
Removed squelch tail from link & set squelch threshold to 0.5uV
Netted TX frequency (was 900Hz low)

Filled batteries with de-ionised water, 2 litres used

Checked operation - HF TX causes distortion on VHF o/p, so replaced old spare control card (without mains fail alarm) but still poor.  Will have to bypass all audio leads to GND with suitable caps.  Leave spare control card in repeater, but with good op-amp in place of LM324

Fitted & wired relay across rectified supply in charger to act as mains fail detector

Checked HF VSWR - still 1.2:1 - OK

1 March 1996 Lady's Slipper ZS2AAW Change repeater and link control cards around:  
DTMF switched card from repeater into link.  
Remove link control card (simple type) to fit mains fail alarm and re-install later.  
Fit spare control card (ex GHT) into repeater

Change 7098 MHz HF Crystasl and nett new one onto frequency

After leaving the mountain, audio is low on VHF repeater and also broken up on louder passages.  Control card has a definite fault
Also forgot to remove squelch tail from DTMF control card which is now fitted into the link, so causing delays on links to/from GHT & Kynsna...

Batteries are low on electrolyte

Mains fail alarm must be fitted to good control card and re-installed ASAP.

23 February 1996 Lady's Slipper ZS2AAW Re-instate the 6m link which was disconnected for the QSO party
No other work done - HF TX is low in frequency again - must replace the 7MHz crystal...
18 February 1996 Spare Repeater ZS2AAW Fit the Squelch and IF boards from Knysna into the spare (mobile) repeater and leave on soak test at home, awaiting the open-squelch problem
17 February 1996 Buffelsnek ZS2RS, ZS2AE, ZS2AZR, ZS2ABZ, ZS2AAW, ZR2EY, ZR2VM, Pat Trip to repair VHF repeater - intermittent SQ open problems
RX audio & IF board replaced with those from spare unit.  SQ control line idles at -5V, open SQ to -4.8V
RX Opens at 0.25uV direct.  After replacing boards, still works to this level
TX gives 5W out of filters, lined up into filter
Quiescent current on 24V line = 0.6A
Removed 4x oven lines, quiescent current now 0.37A
Re-netted frequencies & removed padding cap in George link TX 431.125MHz
Drilled covers to facilitate frequency netting
Link to George will still not nett properly - swings +/- 5kHz either side of wanted point.  Tried changing to ch2, but still no luck.  Left it at ~7kHz low, drifting onto frequency after a few seconds' transmission
Solar panels charge at 5A in full sun, seem OK
Depart at +/- 3pm
13 February 1996 Fedlife Building ZS2AAW Experiments done while at home on test:
RAemove crystal osc oven supply & see what happens to TX/RX frequencies.  After cooling the TX was 8kHz high, remains fairly stable while transmitting
Standby current is reduced from 250mA to 150mA
A useful gain for a solar site like Knysna...
2 February 1996 Lady's Slipper ZS2AAW Re-netted the HF TX frequency to 7098kHz
Removed multi-plug from 6m transceiver in preparation for VHF QSO party on 3-4 Feb '96
Batteries require a top-up - NB
Attempt to adjust VHF squelch, but no real change possible due to high RF in area causing blips on VHF
Set HF squelch to 10 o'clock position (slightly tighter)
2 February 1996 Fedlife Building ZS2WG Wolf removed the UHF repeater for maintenance - low TX power suspected.
TX found to be 2.5kHz off frequency.  Duplexer in grave need of alignment.  Receiver OK
Added 100uF cap + 10R resistor to PTT line as a short squelch tail
Routine maintenance carried out and performance is OK
TX power reduced to 10W out of antenna socket. (final trimmers run very warm at 20W o/p)
On test at 26 Nathan Rd
20 January 1996 Governroskop ZS2AE, ZS2AAW Refit repeater after repairs to TX in PE.  Recoonect aluminium TX filter until such time as the duplexer is tested and returned to site
Repeater back to normal
18 January 1996 Kareedouw ZS2AAW Fit new UHF Yagi towards Slippr, but VSWR is still not good at 1.5:1  However the linking equipment is happy - no self-interference
17 January 1996 Governorskop ZS2AE, ZS2WG, Otto & wife & son,  ZS2AAW 145.750 VHF Repeater
Aim was to install new 6 cavity duplexer as constructed by Wolf & team.  Otto to help with alignment

Duplexer could not be aligned satisfactorily - insufficient rejection obtained, causing chopping on weak signals, even with a tight squelch setting.  SINAD is not good , at >1uV for 12dB

Attempt to tune TX output stage for "minimum noise" and in the process, short out the finals trimming plates, taking out the final transistors!  Repeater is removed and brought back to PE for repairs

12el Yagi to East London re-installed to reclaim my N-type barrel connector.  Link left enabled, so traffic EL - PE unaffected by removed repeater

Wolf also lost a tyre on a hidden tree stump...

Replaced repeater audio interface board with narrow (mobile) version incorporating mains fail alarm - previous control card suffered intermittent low TX audio levels 

14 January 1996 Kareedouw ZS2AE, ZS2AAW Howling interference noticed on links from Knysna towards PE
Found water in coax of UHF Yagi towards Slipper, poor VSWR.
Removed yagi & fitted 1/4 wave magnetic mount on top of container as temporary measure
Link equipment is OK

1996

5 July 1992 Cockscomb ZS2AAW, ZR2BB (Seween Bosman) Water in TX coax, suspected from damaged denzo tape barrel connector.   
Replaced Denzo.  
Replaced TX module.  
Checked SWR, all OK (RX 1.5:1  TX 1.7:1)
Bad battery terminal (-ve) - made wire off under nut

BUT...
Battery seems to be bad - repeater pips soon after use, and tries to lock-out in evenings, but goes into oscillation as bettery volts fall, TX inhibits, volts rise again, TX enabled, etc etc.
Noise/interference on RX caused by TX.   TX coverage is good, but RX is bad due to desense/noise on weak signals

17-18 October 1991 Cockscomb (not visited) - Repeater reported out of action following electrical storm on 17/10/1991
11 June 1988 Cockscomb Tony/Zane, ZS2AE, ZR2EY (now ZS2AAW), ZS2WG, ZS2AO Modules changed
TX, RX and controller modules exchanged
RX antenna Folded Dipole fitted
1 May 1987 Cockscomb ? Repeater box found full of water.  
Dried out the modules.
Fitted repaired original 3dB RX antenna with stainless steel top connector
15 March 1987 Cockscomb - Repeater failed - no Audio talk-thru, lots of noise
31 January 1987 Cockscomb ZS2AE, ZR2EY (now ZS2AAW), Rob Salmon, ZS2AO, ZR2ED and daughter Colleen  TX Replaced
The repaired TX module was replaced and working.  Buffer transistor that had failed also replaced with Motorola M9654/7806

Note: 4WD vehicle not available for Nov-Dec 1986

24 January 1987 Cockscomb ZS2AE, ZR2EY (now ZS2AAW), ZR2AAT, ZS2G, ZS2WG Cockscomb Repeater antenna repairs:
The temporary RX antenna was removed and replaced with the original after it had been repaired following the chopper trip damage.  
The TX was found to be faulty and removed.
1 November 1986 Cockscomb ZS2RS, ZS2RL, ZS2WG, ZS2AE, ZS2AL, ZS2RT, ZS2AO, ZR2ED ?
10 October 1986 Cockscomb ZS2RS, ZS2RL, ZS2WG, ZS2AE, ZS2AL, ZS2RT, ZS2AO, ZR2ED Planned trip was rained out.
11 June 1986 Cockscomb - Repeater failed
7 June 1986 Cockscomb ZS2AO, ZS2WG, ZS2G, ZS2BO, ZS2HG, Etienne Plan is to exchange the RX antenna for a 3dB gain antenna provided by ZS2RS
February 1986 Cockscomb ZS2AE, ZS2AO, ZR2EY (now ZS2AAW) Repeater RX and crystal filter brought back to PE for repair - lightning damage thanks to the temporary 1/4 wave RX antenna not being DC grounded
7 September 1985 Cockscomb - Repeater failed
7 June 1985 Cockscomb ZS2AB, ZS2RS, ZS2AE and XYL Julie Repeater Installed

Chopper arrives:

 

Work Party: ZS2RS, ZS2AB, ZS2AE

 

Work Party: ZS2AB, Pilot (??), ZS2AE

 

On its way to the top...

 

Pre June 1985 Cockscomb ZS2AE Construction complete

COMPLETE UNIT

 

RECEIVER MODULE

 

TRANSMITTER MODULE

 

CONTROLLER MODULE

 

REGULATOR MODULE

 

Pre-1985 Cockscomb build ZS2AE, ZR2EY (now ZS2AAW) Facilities Required:
1)  Normal Talkthrough
2)  Talkthrough off, receiver on
3)  Low battery volts alarm on squelch tail or on TX only when normally activated
4)  Low battery volts lock-out - talkthrough off, with tone reset on RX (from 2 above)
5)  Charge rate readout when requested, by tone on RX
6)  Solid state switching of TX from RX (i.e. no relays to foul up)
7)  Lightning arrestor on RX antenna

PYE Europa boards available.  14V regulator on TX board is redundant - done by solar array regulator.  10V regulator for TX and RX is on RX board.  Move to controller box.  Make RF proof.  TX switching of 10V line is missing from RX board.  To be re-instated and used to switch TX.  Make RF proof.  Use this to inhibit TX in 2 and 4 above

DC Specs:
Using Alkaline (NiCd) cells
Full Dump from Solar regulator = 15V
TX Lock-out = 11.5V
Alarm level = 11.8V

1975 Governorskop ZS2AB, ZS2RS, ZS2RD Repeater Installed - article in Radio ZS:

 

Before time...

 

REPEATER WORK (current)

REPEATER WORK (2015)

REPEATER WORK (2014)

REPEATER WORK (2013)

REPEATER WORK (2012)

REPEATER WORK (2011)

REPEATER WORK (2010)

REPEATER WORK (2000 - 2010)

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