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General control line discussion => Open Forum => Topic started by: Lauri Malila on August 28, 2016, 04:40:06 PM

Title: Fromeco-TNC tachometer..
Post by: Lauri Malila on August 28, 2016, 04:40:06 PM
Hi.
Does anyone know if they are still available? I have been trying to contact Fromeco in many differend ways but they won't answer.

Lauri
Title: Re: Fromeco-TNC tachometer..
Post by: Ken Bird on August 29, 2016, 08:36:08 PM
I just purchased one from Darrol Cady in Billings, MT. hhttp://www.darrolcady.com/Accessories/accessories.htm#TNC

I ordered it a week or so ago and it arrived today.

Ken Bird
Title: Re: Fromeco-TNC tachometer..
Post by: Lauri Malila on August 30, 2016, 09:55:12 AM
Thank you, Ken.
I'll check that one!

Lauri
Title: Re: Fromeco-TNC tachometer..
Post by: Charles Carter on August 30, 2016, 11:51:14 PM
Tom Morris sells them also.

Charles Carter
Title: Re: Fromeco-TNC tachometer..
Post by: Steve Helmick on August 31, 2016, 12:33:06 PM
Tom Morris sells them also.

Charles Carter

Then Stunt Hangar Hobby should have them on the order form?   ??? Steve
Title: Re: Fromeco-TNC tachometer..
Post by: Lauri Malila on August 31, 2016, 01:59:58 PM
Oh well. I placed an order at darrolcady.com. They have lots of nice stuff by the way.
Thanks again Ken!

L
Title: Re: Fromeco-TNC tachometer..
Post by: Lauri Malila on September 01, 2016, 03:43:26 AM
A question, Ken:
Which version of the tach did you receive? After ordering I read the description and it seems to be a model that turns off automatically after some time.. I may be wrong but isn't that one of the modifications suggested by Brett & Co. to Fromeco?
Title: Re: Fromeco-TNC tachometer..
Post by: Ken Bird on September 01, 2016, 01:06:29 PM
Lauri,

To be honest, I'm not sure if my tach automatically shuts off. I haven't left it on long enough to find out.

I'm attempting attach a picture of the tach I received. The readout is because of the florescent lighting in my basement.

Hope this helps!

(http://)

Ken
Title: Re: Fromeco-TNC tachometer..
Post by: Brett Buck on September 01, 2016, 01:19:44 PM
A question, Ken:
Which version of the tach did you receive? After ordering I read the description and it seems to be a model that turns off automatically after some time.. I may be wrong but isn't that one of the modifications suggested by Brett & Co. to Fromeco?

    David told them to use a slide switch instead of the microswitch, so you could turn it on before you started the engine. That was just an annoyance. The functional change we suggested was to remove the reflective window over the sensor so there were no stray reflections. That's what fixed David's early version, and it worked just as well as the original TNC. When they incorporated the change, they moved the sensor well inside the box, at the end of a long, narrow, shiny tube. I don't know if that was supposed to collimate the signal and protect the sensor, but the production version doesn't work nearly as well as the original modification or the original TNC. It's *is* a lot better than the original Fromeco version and vastly better than the cheapies like the Tower tachometer.

    I still see people shoving the TNC and the Fromeco version 3" from the prop. The original TNC will get a valid reading from about 5 feet away in most lighting circumstances, so you don't need to cram it into the prop disc to get it to work.  That's a minor flaw in the current Fromeco version, it has to be a lot closer to get a valid reading. That's almost certain;y because the long shiny tube is creating multiple reflections, and they probably changed the filtering to slow it all down to suppress the spurious signals.

   At least if you get a reading at all, it's liable to be correct. The cheapies will almost always give you something, whether it's +-5000 rpm of correct is another matter.

    Brett
Title: Re: Fromeco-TNC tachometer..
Post by: Lauri Malila on September 01, 2016, 02:32:33 PM
Thank you, Brett.
I'll wait and see what I get :)
Whatever it is, it will be a welcome replacement to the MacGregor one I bought in 1990.

Lauri
Title: Re: Fromeco-TNC tachometer..
Post by: Randy Cuberly on September 01, 2016, 03:19:05 PM
I just ordered one and the way I understood the literature is that the switch to operate the tach was a hold to operate switch and it turned off when released.  I would add that I'm not sure about that but did form that assumption when I read it.  Sounded like a good idea to me!

We'll see when it arrives, I guess!  I just hope it works better than all the cheapie ones I've had in the past.  Especially here in the Tucson heat and bright sunlight some won't work at all and most bounce up and down in readings like a rubber ball when it 105 degrees on the flying circle.

Randy Cuberly
Title: Re: Fromeco-TNC tachometer..
Post by: Brett Buck on September 02, 2016, 11:07:08 AM
I just ordered one and the way I understood the literature is that the switch to operate the tach was a hold to operate switch and it turned off when released.  I would add that I'm not sure about that but did form that assumption when I read it.  Sounded like a good idea to me!

   That was the original design. David and I suggested that it be a slide switch. As far as I know, it's still a slide switch.

    The reason is that when you start the engine, you have to push the button and wait for it to start up. It's not all that bad, but it is irritating. And it's not like the old Tower tach, the battery will run the tach for months sitting in the tool box, and, if you do leave it on and run down the battery, it's a cheap 9V you can get anywhere as opposed to specialty watch batteries that are relatively hard to find, and cost $12. I recall going to half the department stores in Lubbock on a Sunday afternoon trying to find the right kind of watch batteries.

      If the new "shiny tube" version has problems, I can suggest some fixes - remove the sensor, remove the tube, remount the sensor on the very front of the box like the original TNC where it belongs, and run leads to connect the sensor to the circuit board. No guarantees, and it might need ferrite beads or something on the longer leads, but it will solve any issue there is with reflections.

    Brett
Title: Re: Fromeco-TNC tachometer..
Post by: Lauri Malila on September 02, 2016, 03:13:42 PM
Yes, I went through all previous threads about the subject and it seems that they adopted the modifications you suggested in the production model. I hope it is so but if not, it seems quite simple to do by myself.
The sensor seems to be recessed about 1/2" deep inside the tube?
Should I paint the tube inside flat black?

L
Title: Re: Fromeco-TNC tachometer..
Post by: tom brightbill on September 02, 2016, 06:08:36 PM
Yes, I went through all previous threads about the subject and it seems that they adopted the modifications you suggested in the production model. I hope it is so but if not, it seems quite simple to do by myself.
The sensor seems to be recessed about 1/2" deep inside the tube?
Should I paint the tube inside flat black?

L
Lauri,
I painted the inside of the tube flat black then add a piece of carbon tube to extend the aluminum one out about .25" through the clear plastic front. This helped as Brett has described. Also, I added a couple hard balsa .125" square pieces horizontally above and below the switches so that the top of the switches are flush with the wood. This keeps the switches from being moved accidentally.