|Title:||UHF PA Temperatures|
GB3WB Repeater Monitoring System
|Title:||UHF PA Temperatures|
In December 2017 we had a major failure on our transmit mast.
The team have purchased a replacement mast and transported it from Southampton to Weston.
The repeater group have now installed the new replacement tower. It is upright, but at its lowest height as we still need to buy some guy wires to keep the tower safe at its maximum height.
The new guy wires need to be bought as soon as possible, so if anyone can help with a donation that will be fantastic.
Until new guy wires can be bought and fitted the repeaters are running at reduced coverage because of the reduced height of the transmit antennas.
It is now Tuesday, January 16 th 2018 and we still need your support.
If you can help with a donation so that we can put our repeaters back on air properly, then please use the PayPal donate button on this site or use the contact form so that you can use bank transfer or meet up with us.
Any amount will help!
Treasurers bank details:
Please email us once you have made a bank transfer and include your callsign so that we know who has made payments to us.
Repeater supporters who have helped raise funds for the replacement tower Tuesday, January 16 th 2018 :
GW8LGX Stephen HUBNet
G8CZE Frank HUBNet
G1ILB Jon HUBNet
G4PZN Chris HUBNet
M0WTX Stuart HUBNet
2E0DOB Paul HUBNet
G7RPG Peter HUBNet
M0HOY Stephen HUBNet
G7GIK Daniel HUBNet
Here are some photos taken via the repeater site CCTV of the GB3WB Buzzard who has lived at the site for years.
These were taken on Saturday 9th December 2017.
You can now talk World wide via the ALLstar network using your VHF FM radio.
We are connected to HUBNet which is a very busy network.
The repeater is controlled by a tiny raspberry pi 3. This handles the ALLstar connectivity as well as the courtesy tones and logic.
You listen on 145.6875MHz
Use a -600 KHz Split
You transmit on 145.0875MHz
Our UHF FM repeater GB3WB has the same raspberry pi 3 ALLstar system fitted.
You listen on 433.300MHz
You transmit on 434.900MHz
At the end of each transmission or ‘over’ the analogue repeaters will send one of three CW (morse) letters.
They will send an ‘L’ (.-..) if the last user was a local RF user and the repeater is connected to the ALLstar network.
The repeaters will send an ‘I’ (..) if the last signal was originating from the Internet.
The repeaters will send a ‘U’ (..-) if they are not connected to the ALLstar network and the last user must have been a local RF user.
GB3WB automatically disconnects from ALLstar at 21:00 until 22:30 every night to allow the repeater to be used for a regular net which is run from the Cardiff area and this net has become a great part of GB3WB. During this time GB3WE is still connected to the ALLstar network, so please use this repeater for ALLstar contacts.
When ever using the ALLstar network please always leave a four second pause between transmissions as this allows the nodes and repeaters to reset. This four second gap also allows others to break into the conversation.
Our two Allstar repeaters are connected to the HUBNet UK network.
Please get in touch using our contact form if you think that any of our 5 repeaters are not working.
|Title:||GB3WB Weather Station|
We have fitted a new weather station at the repeater site, have a look at its own page here:
If you cannot see the weather station displayed above and you are using an iPhone or iPad then download the browser called ‘Photon Browser’ from the app store as this will allow you to view flash on all web sites!
In the photos you can see two of our miniature cyclone windows 10 PC’s.
One runs the weather station and one runs our fusion Wires-X system for GB7IS.
These really are very tiny PC’s!
GB7WB is our DMR repeater which is connected to the Brandmeister network.
We are using a Yaesu DR-1X repeater with an MMDVM KI6ZUM board and TCXO on an Arduino Due plugged into the rear 15w HD connector of the DR-1X.
The MMDVM is run by a tiny Raspberry Pi 3 computer with the KB5RAB image installed.
You can now operate through GB7WB on 439.4875 MHz with a -9 MHz shift using DMR.
On DMR use timeslot 2, talkgroup 9 and colour-code 1 to talk to the World via the brandmeister network.
The local chat channel is on TimeSlot 1, TalkGroup 235145, colour-code 1.
If Budweiser made repeater sites this is what they would look like!
This is the Weston repeater groups cabinet July 2016, only one of the Yaesu repeaters is being used for fusion! One is FM only and two are used for MMDVM:
A Decibel Products 4 channel hybrid combiner is now used to combine all 4 of our UHF repeaters transmitters so only a single antenna is required!
This is a very expensive piece of equipment which we had to import from the USA.
It was well worth the expense as it works so well.
Motorola MSF5000 TLE2522 UHF Amplifiers are now used on our repeaters, because of the massive losses in our 4 channel Decibel Products hybrid combiner which we use to allow all of our 4 UHF repeater to use the same antenna.
In total our Decibel Products hybrid combiner and two TX notch filters put about 10dB of loss into our transmit path.
To get 1w out we need to run 10w and to get 10w out we need to run 100w!
That is why we need big reliable amplifiers which require only 3w of drive to produce 100w.
All of our repeaters have been reprogrammed to run only 3w now which means their PA’s are just ticking over and not even getting warm!
We have also fitted Big 50 Amp ACS758 current sensors to our amplifiers so that our Arduino Mega web server can measure and display the amplifiers performance on a web page.
We have also attached a 7 segment voltmeter display to the green wire in the 6w molex socket so we can see the TX output power forward voltage. This forward voltage is around 8.8v when the PA is running 100w.
The red wire in the socket is connected to a 100k thermistor mounted on the heatsink to allow you to measure the PA’s temperature. Measure between the red wire and the black wire which is ground.
The brown wire is connected to the 100k thermistor mounted on the dummy load of the circulator.
Keep up to date and fully informed by joining our Yahoo Group: email@example.com
The only place to find out what is going on with our repeaters is at our Yahoo Group: ‘IT-IS-WB-WE’ so do join today and don’t miss all of the latest news!