Photos of the insides of Fine Offset sensors.

[Gina]

Having recently bought a second FO station kit from Maplins I've noticed a few changes in the design of the rain gauge. These two photos show the differences.

Top view with the covers removed. Two differences - stops for the buckets and maybe some protection against spiders etc. by a grid of 6 small holes below each bucket versus a great gaping hole. I think the problem of wind blowing underneath would be lessened too. (New one at the front.)

new1.JPG

And this shows the underside with the new one at the bottom

new2.JPG

[wd40]

That is interesting on the wind entering the older, large, open drain. I just got mine a couple of weeks ago and it too has the grid like your newer model.

[geoffw]

That is interesting on the wind entering the older, large, open drain. I just got mine a couple of weeks ago and it too has the grid like your newer model.

I must take a look at the replacement I had from Maplin a few months back!

[MartinDn]

Mine was purchased in July, and has the grid.

[firedude52]

Great info! thanks!

Tony
http://morrobayweather.us/

[ben-s]

I've just bought a spare W8681 transmitter because I want to try some mods without breaking my station.
I'd like to take the sensors off the board and put them in the screen, with the main PCB re-cased and put elsewhere. I'd like to get better airflow over the sensors to see if I can improve the response time.

When I opened the case up, I discovered an update to the design that I've not seen listed anywhere else - the DCF antenna is now properly attached into the top of the case with a sensible amount of glue and a couple of foam spacers prevent the PCB rubbing on the coil.

My new Tx is the solar powered version, but looking at it, it seems the only real difference is in the screen, which has a mount for the solar pod on top. Power is fed to the Tx via pins 3 (-) and 5 (+) of the Rain connector, and the rain sensor plugs into the bottom of the solar pod.
Testing on my bench under a halogen desk lamp, the solar panel puts out between 5-6V open circuit.

I've attached a photo of the new DCF antenna position as well as both sides of the PCB for comparison with older units, and a labelled pinout for the solar pod cable.

[Gina]

That's very interesting Thank you for posting the photos

[ben-s]

Just opened the solar pod up, nothing particularly interesting in there, a simple white masked PCB with the solar panel's support frame screwed to it.
The PCB has an RJ11 type socket for the rain sensor, a small tactile "reset" switch, which seems to short out the panel momentarily, and a captive lead with an RJ11 plug for the Tx.

There is a moulded 2x AAA battery holder in the bottom of the pod, under the PCB, but no contacts or batteries are installed.

This Tx kit was supplied with a pair of 2000mAh rechargeable batteries - labelled "rechargeable alkaline"
I don't know whether I'd trust that label, I've seen so called rechargeable alkaline cells before, and they leaked when recharged.

Pics for reference. If anyone feels like building their own equivalent panel, let me know and I'll draw up a circuit diagram and pinouts.

[Orion]

And a couple of photos of the anemometer

[mr.sneezy]

Does anyone here recognize the Logo on the RX module or know any maker information ?
A search on Google Images came up blank.
Crop of the RX module attached.

Thanks,
Martin

Edit: I think I just got lucky with Google...
http://www.hoperf.com/upfile/RFM01.pdf

Edit2: Looks like they make all the main sensors in the wh1081 !

[Gina]

That's interesting Thank you for finding the info I thought it probably used FSK. That's Frequency Shift Keying for those who don't know. One frequency is used to transmit data 0 and another for data 1. This is a common modulation method for radio/wireless data transmission.

[Orion]

Nice find Mr.Sneezy
Here is the link for the transmitter
http://www.hoperf.com/upfile/RF02.pdf
Also Antenna info
http://www.hoperf.com/upfile/ANTENNAS_0102.pdf
And Pressure Sensor
http://www.hoperf.com/upfile/HP01S.pdf

[mr.sneezy]

Nice find Mr.Sneezy

It was a bit of luck. I was searching through general 433Mhz module datasheets and I noticed something familiar in one of them. It was the parts layout on the board, matched the posted photo here exactly. Then the 'bingo' moment

I have had a search around at using the module. They are a bit tricky to use, but it's been done by a few tinkerers so it's doable.

Now to see if I can find a cheap source that will sell one or two at a time. Then write some PIC MCU code (and post it here of course).
Martin

[Philip]

Have just had to replace the bearing in the anemometer, the old one felt like it had a lump of grit in it and had an intermittent tight spot. New one came from simply bearings for the princely sum of £2.29 plus £1.50 post.

part number MR105.2Z simplybearings.co.uk

Philip

[Orion]

Wonder how easy it is to replace the bearings as it seem only to be held in place by melting the plastic
perhaps it would be possible to use a screw and a couple of washers
could you post a photo when you have done it
nice link by the way