My VM109/108 receiver/sender works as intended but only at very close range, and not at all from the car as was my intention. I have tried extending the short blue receiver antenna wire to a tree with a coaxial cable, but that does not increase the range at all. What to do? Would an antenna amplifier help?
An antenna amplifier will not help. Try moving the receiver. Keep it away from transformers/motors/metal parts/ cables/ etc…
Extend the antenna with a piece of wire, not a coaxial wire.
Hi,
I’ve used the old K6727/6706 several times and if well adjusted they all have a good range. This week I installed for the first time the PIC version of the VM109. Even after adjusting (with scope on LIN output of RF module, adjust coil to max signal when TX pressed on a distance of approx. 10 meter) the range is unusable. It seems that the signal conditioning (analog to digital) somehow influences the timing because even with a good amount of signal left and the digital output showing nice square waves the module won’t switch. Anyhow…it doesn’t work until in range of +/- 5 meter open space and +/- 1 meter through a brick wall. Anyone similar experiences/solutions or is the RF module bad?
Grtz…
This is strange.
If you wish, you can return your unit (or just the RF receiver module) for inspection.
Please return it to:
Velleman Projects Tech. Dept.
Legen Heirweg 33
9890 Gavere
Belgium
Seems I have the same problem as lespinoy. In the most ideal circumstances I get a range from oprx 5 meters. But wen I’m on the other end of the wall (i use it as a garage door opener ) I need to be in less then 1 meter. Have tried to extend the range by extending the antenna wire with similar wire of 2 meters but that does not extend the range at all. I was now considering buying a “real” antenna for this frequency but have bumped in this forum. I would appreciate feedback if the problem from lespinoy gets solved.
Greetings.
Today I went back to the shop where I bought my VM109.
They exchanged it with a new one (I’m a good customer there, that helps ;-). I tested it here in my workplace and it seems to work better but not as good as the old ones (I know the range of the old ones since they had to be adjusted). Next week I will reinstall the new unit and post a reply concerning the outcome…Grtz…
Ps.:Thanks for the address VEL417, this might come in handy in the future 
I’m sure something is wrong with the reciever. Have tried with all tree transmitter I have bought bu no joy.
VEL417: Can I send it to the adress? I would apriciate a inspection verry much.
You can return your unit to the above address for inspection/repair.
Well, I’m back…
I installed the new unit and there was an improvement but not that much…
The range through the brick wall (and garagedoor) went up to approx 3 meter.
Just for testing I took an old spare unit and installed it on the same spot. The good old discrete components receiver had a nice sure range of more then 10 meters!!! It worked up to 15 meters but then sometimes I had to push the transmitter several times.
I is a bit regrettable…Velleman did not know the saying: “never change a winning team”. The only thing I can do now is find another remote or try building the pcb (at least the HF part) of the old unit’s myself; but I’m a bit concerned if building them myself is legal…
Perhaps VEL417 can come up with a fix to improve the range ? I cannot imagine that they don’t know this problem. Maybe an idea: just start reselling the old ones parallel to the new ones
Grtz to all…
Hi Touran,
The link doesn’t work so i can’t look and see if it could help 
I was hoping that VEL417 would reply on my “range improvement” question…
Well, perhaps with all the hollydays he didn’t have the time yet…
Understandable, my rhythm is disturbed also
Grtz…
Appreciate your input. 
If you want to have a look at the antenna I was talking about: Its in the “conrad catalogue” www.conrad.be number is 190073 - 8A
Looks real cool 8)
tanks
Nice antenna…
A pity though that there is nothing in the datasheet to get an idea of the gain, sensitivity, receiving pattern, etc…
Without these specifications it’s hard to tell if it’s a good antenna.
However, it should not be necessary to mount an external antenna costing 25 euro…
The old Velleman units had a good working range of 20 meters and more without problems!!!
I don’t have the unit anymore (it’s installed) but I was thinking, in the transmitter they use a blue led now instead of a red one…
Perhaps the Uf of this led is higher then the red one so you would lose that voltage for the transmitter hence the RF power…
Some experimenting would be in place now ;-D
Grtz…
Ps. Have a nice and happy Newyear!!
There is no point in getting an antenna, as the VM109 is not equipped with an input for a dedicated 434MHz antenna.
The blue led is not the problem either.
For the record, we had to discontinue the old units because the decoder IC was no longer available. Furthermore, we got too many returns because for some people, constructing the RF receiver part was too difficult. Therefore it has been replaced with a module. The transmitter had to be changed too, to comply with new laws.
The range depends on the environment. Sometimes, moving the reciever 50cm helps a lot. Keep it away from metal parts, cables, electric fields, motors, transformers etc…
If the problem persists, please return unit for inspection.
I just bought this kit VM109 plus an extra VM108 to replace my old remore control for the garagedoor.
I was very dissapointed when it did not work from within the car and I even got more dissapointed when it did not even work from outside the car 4 meters away from the reciever.
The only object in between was a wooden garagedoor!
No metal mush or anything arround the receiev that could disturb!
However I found out that the temperature was affecting the receiever, in Norway we usually have some minus during winter and the last few days it has been varying from -6 to -14
So for me it is useless and I will return it to the shop
VM130, which is indentical to VM109 features built-in heating.
http://www.velleman.be/be/en/product/view/?id=375928