Sinar spear for when it is in the shed. Very good. Ancient Protimeter model for grinding it up. Probably 25 years old, but reliable. Cost very little new in 1984, so why skimp on something that will last forever? You can calibrate it simply, so will never fail. Otherwise, I just bob a kilo bag down to my local merchants lab (5 mins drive away). Thats cheapest.

Thinking of others, neighbours have one of those what looks like a fancy cup, with a handle and display on them. They're quite good.

I still like the old marconi best.If it falls out of the compressed cell on its own its dry.£5 in a sale new batterys and your away. JOHN.

Where can you get new batteries ? The tall round one is not made anymore, so I'm told and the 45v has to be 5 9v connected together. Some have been converted to mains but again where can it be done ? My Marconi has been on old barreries for several years so I expect failure every time I use it. The upside is that you only need a few ears to do a test whereas my Sinar needs 2 cups full. 

      I still use an old Marconi, circa 1965, It is still deadly accurate. I test it against the grain merchant's each year. My local electrician converted it to mains electric about five or six years ago. It is still very accurate but the zero setting is a little more sensitive.

Try Dr Egleton at www.marconi-moisture-meters.co.uk . I take my Marconi to him for servicing and I think it was him who got it converted to mains power after I had difficulty finding the batteries. He lives in Lincolnshire. If that's not close by then you might have to courier it to him once harvest is over. That's if it ever stops b####y raining! 

 01775 711800 is his number.

Good luck. Steve

Excellent, thanks Steve, I've been trying to find a mains conversion for ages. A trip out next week .

I inherited a 1947 Marconi from my old Dad.

It's always been pretty accurate, but this year nothing off the combine seems to register on the scale.

Any ideas ?

Three weeks later, and now nothing coming off the drier seems to register on the scale.

So much for British engineering.

I would recommend Protimeter. I bought a Sinar Farmpro 3 years ago and when I took it to a moisture meter clinic it's readings were erratic. Sinar didn't want to know - tried billing me for taking a look at it even though it was still under warranty and never did sort it out. I had so many claims on wheat in the year that I cut my losses and replaced it with a Protimeter Grainmaster i (about £300) and am very pleased with it.

Sinar spear broke yesterday. Seems the bullet tips have a rather shorter life than the grind-it-up type. On the other hand, they could figure it out over the phone and have arranged to have it collected, fixed, calibrated and returned. Will cost but at least service is good.

Apologies to the shades of British engineering.

One dry day and wheat just off the drier is now on the scale (59 -  27%).

Back to normal, thank goodness.

you need something you can rely on and is easy and cheap to calibrate. whole grain ones are good (Sinar springs to mind) and avoid grinding (particularly with beans and oats).

 See this for getting good moisture meter

http://www.processsensors.com/

I would avoid M.Lishman. I had a meter serviced there last year, used it for about 2 weeks during harvest, I opened it to replace the battery this year only to have a wire fall out of because of poor soldering.

I contact Lishman who tell me that shouldn't happen but they dont have time to put solder the wire back on until after harvest. I have since phoned then and asked to speak to Gavin Lishman who I believe is now the manager. I was told he would ring back. Nothing has been heard from him.

They service is appalling

bankrupt:

 

I inherited a 1947 Marconi from my old Dad.

It's always been pretty accurate, but this year nothing off the combine seems to register on the scale.

Any ideas ?

 I know its much nicer when they do as you don't have to worry about replacing it. Saying that some of our fence stakes from 60 to 70 years ago are in better shape than ones brought 6 to 7 years ago

 Hi wagstaf. It is worth considering the Dickey John MiniGAC. Its a whole grain tester with adjustable calibrations. Its build quality is far superior to the Sinar. I have worked with Martin Lishman Ltd for many years and know the reputation for the Sinar is poor. If you would like a price on the MiniGAC, I would be more than happy to supply you a price.

 If you are thinking of repairing or calibrating your Sinar, its worth sending it to Dry-It-Out in Leicester. Its cheaper than Sinar, and its where we send them at Lishmans.

Hope this helps.

see www.agquipsolutions.co.uk

Regards

Ben

Hello I'm a student Liverpool John Moores and I'm replying to your post because I believe you know the inner working of a grain moisture meter. For my final year project I'm trying to make a moister meter but i'm struggling to figure out how it works? I was thinking about using electodes to take measure the sample but i'm not sure how it works.

Any infomation and i'll be greatful

Thanks

James Padget

James, this thread is over a year old ! i doubt that many of us understand the inner workings of a moisture meter, I certainly don't !

 Presumably a small current is passed through the sample and conductivity or resistance is measured between the electrodes. How that translates to a moisture content would take several physics lessons to understand. If you are going to try and make one consider how the reading would vary betwen crop types and whole or ground samples.

You can easily make one, James Padget, if you need to.

The circuitry of the Marconi, and of some others, is a simple Wheatstone Bridge, named after the fertile physicist Sir Charles Wheatstone (1802-1875).

As you will know, a Wheatstone Bridge determines the electrical resistance of a sample on test by noting the setting of a variable resistance (rheostat) when no current flows through the open bridge. Clearly, at this moment, the ratios of the voltages of the bridge's two power sources exactly match the ratios of the said two resistances.

The voltages of the two power sources being known, the resistance of the sample can be read off the rheostat, moisture content as a known function of resistance being built into the conversion scale provided.

Clearly, the accuracy of this arrangement increases with the ratio of the voltages of the two power sources (45:1 in my Marconi). Hence the well-rehearsed difficulties posed by the requirement for power sources of one uncommonly high, and of one very much lower, voltage.

However, you could make a workable meter, albeit not a very accurate one, using, say, 12v and 6v power. 

Best wishes

Bankrupt