gb3wb

To keep GB7WB on the air we have recovered as much of our damaged tower as possible and fitted its UHF 8-Stack to it.

Also we are using G4KLX’s split repeater software to enable us to use two separate receivers to provide site diversity.
The second receiver is in Worle to provide some additional receive capability.
Jonathan’s software automatically selects the best GMSK data from which ever receiver provides the best bit error rate.
Hopefully this will make up for the low height of the GB7WB 8-Stack.

On Sunday Morning 29th April 2012 our main tower suffered massive damage in the high winds.
At 5.22 am the lower part of the latice tower folded which caused the whole tower to fall into a nearby tree.
Amazingly not a single antenna or feeder was damaged and even the wind turbine and blades are in perfect working order.

In order to keep all of our repeaters on the air we have moved GB3WE’s folded dipole onto our small wind turbine mast. This mast holds the GB3WB 4-Stack already, so its coverage is unaffected.

To keep GB7WB on air we have had to temporarily fit a colinear to the very short remains of the damaged tower, so it is practically at ground level. Obviously coverage will be well reduced, but at least GB7WB is still on the air.

It was a very big and dangerous job to get the whole tower and turbine out of the tree. But to make the area as safe as possible as quickly as possible we have worked on the site more or less night and day for three days in some terrible weather conditions.

Here are a selection of photos of the damaged tower.

One of the site cameras has been set up inside the tree again to watch the great-tit nest. There are another pair nesting in the massive tree near this regular nest this year too.

Here are a few snap-shots from the live video feed which you can watch regularly on our live video link here.

GB7WB Fan Control Thermostat Modified & Fitted.
The thermostat we had only had a ‘normally-closed’ contact and we needed a ‘normally-open’ contact to put the 24v fans on when ever the repeaters got too hot.
With three FX5000 repeaters stacked on top of each other, with their six combined crystal ovens and three power amplifiers etc you would be surprised just how hot they get!

A grub-screw was removed which was fitted to provide a rest for the center contact of the bi-metalic strip. A small screw with a solder-tag and wire was used to replace the grub-screw and the wire was attached to the spare solder post.

Now we have a single-pole, double-throw set of contacts and the fan switches on when the temperature rises.

The Weston Repater Group recently completed a new dual-mode D-Star GMSK ircDDB & FM repeater for Plymouth. GB3IE is now on test in Plymouth, and will hopefully be in full dual-mode service very soon when its new NoV arrives.

All of our FM analogue and D-Star GMSK DV-RPTR repeaters are now using FX5000 base-stations.

GB3WE GMSK D-Star Repeater Using DV-RPTR Modem
Audio control board details

GB7WB & GB3WB Both Using DV-RPTR Modems For GMSK D-Star.
Both of our D-Star repeaters have now moved over to DV-RPTR modems and are controlled by Jonathan Naylor’s latest beta software.
Get more details of the DV-RPTR modems here: http://www.dvrptr.de/
Find out about Jonathan’s G4KLX repeater software here: http://db0fhn.efi.fh-nuernberg.de/~g4klx/
Both repeaters are operating better than they ever have and don’t suffer from any problems.

While using either GB7WB or GB3WE Use Your DTMF Keypad To Connect D-Star Reflectors …

The available commands are:

# for unlinking
0 or 00 to trigger the info message
*1C or *01C or *001C to link to REF001C
1A or 01A or 001A to link to XRF001A
D5B or D502 to link to DCS005B

The GB3WE VHF repeater suffers tremendously from ‘metal-on-metal’ interference as all repeaters do. This interference is noticeable on any weak signals accessing the repeater and sounds like a constant crackle and almost as if a microphone has been placed next to two pieces of metal while they are being rubbed together!
This is caused by the repeaters transmitter constantly transmitting its energy into all nearby metal objects and the receiver being able to detect the making and breaking of any conductors which are allowed to freely move across each other.
Every conductive object must be either securely fixed to any adjacent conductive object or insulated completely from the other objects, the important thing is that they must never rub together.
Our guy wires were our biggest problem, so we had to devise a way to insulate them from the tower and each other to remove the interference that we were suffering from.
It didn’t help that we have a three section wind-up tower with a very heavy wind turbine mounted on the top, which caused the tower and guy wires to move continuously in the wind!
Cutting the Gordian knot!   …..  The photos show how we overcame the problem.

Here is a short video to show you how bad the interference is when a weak signal is accessing GB3WE and metal objects are allowed to rub on the guy wires

In the tremendous winds of the morning of 05/01/2011 at 1am the tail was broken off of the GB3WB wind turbine. This had the disastrous effect of stopping the turbine from auto-furling.

This left the blades facing the wind, which caused them to spin at thousands of RPM until they were all broken off. This is a disaster for our repeaters.

It is worth noting that our modified oil-filled heater 24v dumpload worked perfectly day after day and saved our expensive battery sets from over voltage charging and burning out.
Other repeaters running from wind turbine power not so far away lost their dumpload, which in turn destroyed their battery sets. They also lost their mast and antenna. It was a real nightmare for us all!

We have currently turned off the repeaters to conserve the power in the batteries.

A new tail and set of blades will have to be bought and fitted asap so that the repeaters can be activated again.

Click on the play button below to watch a video of what is left of our turbine.

The GB3WB guard dogs prove more expensive to keep than first thought!

GB3WE GB3WB GB7WB New Configuration. GB3WE & GB7WB are ircDDB STARnet Digital Group Calling enabled D-Star repeaters.

GB3WE is the top mounted dual-mode VHF FX5000 D-Star GMSK/FM repeater.
GB7WB is mounted in the middle and is a UHF FX5000 D-Star GMSK Node.
GB3WB is mounted at the bottom and is a UHF Key Repeater for FM.

GB3WB New Guard Dogs

GB3WE and GB7WB FX5000 Repeaters. GB3WE at the top in brown is our VHF 2m dual-mode D-Star (GMSK) and FM repeater. Underneath is GB7WB, our UHF 70cm D-Star (GMSK) repeater.

GB7WB FX5000 UHF D-STAR GMSK Repeater

GB7WB Modifications to FX5000 Transmitter For D-Star Operation.

To modify an FX5000 VHF or UHF for D-Star GMSK operation simply add a 47nF capacitor across C493 (22nF) which is next to IC403 (TL072) in the transmitter driver module.
Then remove C536 (10uF) which is next to IC504 (LM324)

No modifications are necessary to the receiver module.

Wireless DoorBell Mixing Interference Shown BY G3SDH.

Due to the terrible wideband local oscillator in the cheap wireless doorbells we are finding more and more cases of transmissions appearing on frequencies where they shouldn’t be. In fact it turns out that any 70cm signal can easily be mixed by the doorbell and the original signal can now be found somewhere else in the band as well. 
 

GB7WB October Sunset

GB7WB Raptor At Tea Time

GB7WB Wind Turbine Tail Blue camouflage Pattern Detail

Hot Air Balloon Passes GB7WB In Front Of Glastonbury Tor

GB7WB Brand New UHF FX5000 Repeater

GB3WB Very Early Morning

GB3WB G1VSX Getting His Leg Over

GB3WB G1VSX Sunrise Tower Climb

GB3WB Wind Turbine Test LEDs which are used to test our new 12 way slip-ring mounted at the top of our tower.

GB3WB Wind Turbine Modifications. The GRP blades have now been balanced. New tail pivot spring brackets have also been fitted. A second 12 way slip-ring has been fitted inside the main 3 phase slip-ring so that other equipment may be fitted onto the turbine to monitor its preformance or send other data. At the moment LED’s have been fitted to each circuit to test them.

Here is our new replacement FX5000 UHF repeater for GB7WB

GB3WB DumpLoad Controller Lives!

GB3WB Wind Turbine Tail Pivot Spring Details

 

 

GB3WB with Boeing 747 a few hundred feet above the mast breaking through the clouds.

 

GB3WB 500w Oil Filled Dump Load

 

 

GB7WB Mast Configuration October 2011

GB3WB New Wind Turbine Blades Fitted

GB3WB Current Mast Configuration With New GRP Turbine Blades

GB3WB Getting The GRP Blades Fitted

This is what the new wind turbine blades look like. These will be fitted at the weekend.

GB3WB wind turbine blade failure worked on in the dark in 50 mph winds

 

Detailed View of Damaged GB3WB Wind Turbine Blades

GB3WB Graph.

View WB graph in its own window

GB3WB Video Files Player

 

GB7WB at sunset

GB7WB Turbine view of Glastonbury. Now that our highest omni antenna and wind turbine have been swapped over, the turbine can just see over the tree which has blocked most of the wind from us for such a long time. Our two towers are still at the same height, simply the head-loads have been swapped over. The omni antenna is now on our lower mast and our wind turbine is on the taller mast.

GB7WB and GB3WB 2011 Antenna Configuration

 

GB7WB Repeater reconfiguration on an August evening

GB7WB and GB3WB site having its coax feeders fitted and terminated by the feeder team, G1VSX, M0RHV and G3SDH.

Original Wind Turbine after overhall, with new slip-rings, silent blades and new colour scheme.

GB7WB turbine blade silencing details, showing garden strimmer cord
see full details on how this is done here 

GB3WB Original Wind Turbine Sprayed. Now that the wind turbine blades have been silenced by the modifications found here we have opted for a blue camo finish in place of the original dark green option.

 

GB7WB antenna’s being rigged by Steve G4TBD & Graham G1VSX

 

GB3WB tower being modified and welded by G1VSX.

 

GB7WB Wind Turbine Slip-Rings

GB3WB Map of Web Site Visitors