What is a good tachometer to purchase?

[frank mccune]

     Hi All:

      What would brand of a tachometer do you reccommend?  It is time to retire my 1973 Heath Thumb Tack and move into the digital age. Lola

      What are your thoughts about the Hobbico and Glow Bee tacs? They appear to be very popular.  Are there "better" tacs?

                                                                                       Tia,

                                                                                       Frank McCune

[Brian Massey]

I use the Hobbico and have been completely satisfied. I use it as a reference point, so if it's off a tad, I'm not aware.

Brian

[Steve Helmick]

Hanger 9 Mini Tachometer is popular here. It's also what I use. They're about $28 at the LHS.  Steve

[Motorman]

I use the hobbico tack and it works great. I find if you take the batteries out when not in use they last much longer.

MM

[Perry Rose]

To check the calibration of these types of tachometers just turn it on and point it at an electric light bulb. It should read 3600. Using one anywhere near an electric light can cause erratic readings. Outside is best.

[Keith Miller]

I like the Glow Bee.  It has three memory positions and can do 2, 3 & 4 blades.  The only downside is that, when they get warm (like sitting in the sun), the LCD display goes very dark and is difficult to read.

[frank mccune]

      Hi Perry:

      I do not think that one can calibrate a photo tach via an incandescent light source. It must be a fluorescent light source that pulses at 60 hz. to get a reading of 3600.  An incandescent lamp does not pulse.

     I have always used sunlight or a dc powered light source when using a photo tach.

                                                                    ymmv,

                                                                    Frank McCune

[Will Hinton]

I use a Glo-Bee and like it fine.  I always lay it upside down in the flight box and don't have any problems with the LCD display going dark on me.

[Brett Buck]

     Hi Perry:

      I do not think that one can calibrate a photo tach via an incandescent light source. It must be a fluorescent light source that pulses at 60 hz. to get a reading of 3600.  An incandescent lamp does not pulse.

   The TNC (original, or Skyborne version) has no problem picking up the slight variations in an incandescent lamp. I don't know about the current Fromeco version.

     The first Fromeco "TNC" had all sorts of problems, even on propellors. This is the one with the sensor behind the solid front windowl. David modified this version based on my advice, and then Fromeco adapted the mod and offered it for other people. That worked as good as the TNC.

http://www.clstunt.com/htdocs/dc/dcboard.php?az=show_topic&forum=103&topic_id=194150&mesg_id=194150
 
   The second/current Fromeco version with the sensor deep inside a shiny tube is reported to work OK, too, but the sensor really needs to be where it was on the original TNC.

   If it was me. and I needed a tach (which I don't, since I have an original TNC that I still use, and two Skyborne version that I have as backups), I would get the latest Fromeco version with the long skinny tube and the slide switches that stay in place (as opposed to the spring-loaded type that you have to hold to keep "on"). If it seems to have problems, I would modify it to move the sensor to the front by removing the tube and sensor, taking the sensor out of the tube, and mounting it to the front like the TNC.

   We used to have all sorts of problems with tachs, but Bill Fitzgerald found the TNC and all of that went away. My original is probably around 20 years old and with minor maintenance it still works as well as ever.

    Brett

[Gene O'Keefe]

I have 2 of the original TNC tachs ( one brand new never used ) that I would be willing to sell - PM or email me if interested.   Thx.

[FLOYD CARTER]

I often pit for flyers who use a "tach".  I watch them and also watch the reading.  Usually varies from 9600 to 9950 for no good reason, while I can't detect any change in the engine note.  They seem happy, but I can't figure why.

I have a GloBee tach, but my calibrated ear is more accurate and more reliable.

Floyd C.

[Tim Wescott]

I often pit for flyers who use a "tach".  I watch them and also watch the reading.  Usually varies from 9600 to 9950 for no good reason, while I can't detect any change in the engine note.  They seem happy, but I can't figure why.

You get used to guessing the truth in the noise.  My calibrated ear isn't good enough for me, so I need the tach.

[Steve Helmick]

      Hi Perry:

      I do not think that one can calibrate a photo tach via an incandescent light source. It must be a fluorescent light source that pulses at 60 hz. to get a reading of 3600.  An incandescent lamp does not pulse.

     I have always used sunlight or a dc powered light source when using a photo tach.

                                                                    ymmv,

                                                                    Frank McCune

Incandescent works fine in the USA. Some countries do use 50 hz., which would throw a crowbar into the mix. They'd show 3,000 at 50 hz.  Steve

[Brett Buck]

I often pit for flyers who use a "tach".  I watch them and also watch the reading.  Usually varies from 9600 to 9950 for no good reason, while I can't detect any change in the engine note.  They seem happy, but I can't figure why.

I have a GloBee tach, but my calibrated ear is more accurate and more reliable.

  This is why everybody gets a TNC of some sort eventually.

    Brett

[Steve Thomas]

I got a tacho app on my smartphone, and never bother with my regular tach any more.  It gives identical readings to a friend's Fromeco unit, but isn't light-dependent and doesn't have to be anywhere near the engine.   It's not perfect, but few things are.

[George Hostler]

It must be a fluorescent light source that pulses at 60 hz. to get a reading of 3600.

Older magnetic transformer type ballasts pulsed at 60 Hz. Some may not be aware that the newer electronic ballasts pulse at 20 kHz or higher. Even replacement ballasts nowadays may be electronic. In our kitchen just replaced the old magnetic T-12 ballast with a newer electronic T-8 one (and installed T-8 bulbs. T-8 uses same mounting pins as T-12). Lights are now brigher.

[tom brightbill]

FYI-  I talked to Fromeco this morning and they will be doing another run within a couple/few weeks.  They have the parts, and have the assembly time scheduled. I did not confirm the recent price, but did notice during a search last night that it was $95 a year or two ago. They have orders for some hobby shops, but offered to take an order for me (but I've already found one elsewhere). Check their link:

http://www.fromeco.org/products/05frctnc/

[Tim Wescott]

Hey Tom -- can I take yours apart when you get it, and look at the innards?  I promise I'll get most of the pieces back together, close to where they started.

[bill bischoff]

I like the Globee since it use a "buy one anywhere" 9 volt battery. It's also big enough and red enough to notice when you leave it on the ground.

[Brett Buck]

I like the Globee since it use a "buy one anywhere" 9 volt battery. It's also big enough and red enough to notice when you leave it on the ground.

   Using a regular, normally available battery is pretty important. That was one of the big complaints about the Tower/Hobbico back in the day, it took $12 worth of watch batteries that you had to go to a jewelry department to get (at least at the time). One of the good things about the TNC was the 9V, and the supplied battery looked like something from the Eisenhower administration, but lasted me for something like 5 years.

   Brett

[Larry Renger]

My electronic genius brother built me a crystaal controlled tach checker. Good up to 60,000 rpm. Every tach I have checked has been right on athe money except for one TMC tach that was 5% off. I am guessing that they all are crystal controlled these days. 

[Bill Johnson]

I bought a GloBee tach from tower Hobbies shortly after this initial post. It lasted 3 uses while breaking in some engines but failed on the forth use at the flight line. When turned on, all display cells light up and it won't clear or give any reading.

Tower Hobbies has discontinued it so they are crediting my account. It looks like I'll be looking for a TNC tach.

[John Leidle]

 I bought a new Red Hobbico in July & the only thing it did consistently was drain the battery POS  . I sent it to the Happy Hunting Grounds.
                        John

[George]

I got my TNC directly from Tony and it still works fine. I understand that FROMECO updated the tach because of parts availability.

George

[john ohnimus]

Glo Bee for me. Had mine about 18 yrs.

[Carl Cisneros]

Got a Glo Bee one about 6 mons ago.
mine and another flyers tach (same model) just gave up the ghost.

[PerttiMe]

I got a tacho app on my smartphone,

Which one?

[Brett Buck]

I don't have one but the latest Fromeco version is supposedly serviceable, although not nearly as effective as the first version Fromeco with the modifications that David made (at my suggestion). Bascially, we removed the supposedly transparent (to IR) window that sits over the sensor, so it was just sitting there bare.

   If I had to start from scratch today, I would get the Fromeco, and if there was any problem with sensitivity or it has to be too close to the prop, I would modify it.  I would remove the sensor and the tube it sits in, and move the sensor to the front with a short and wide baffle like the TNC. It is not a simple project, the way it is put together, because it is buried deep inside unit. You need the baffle because it is sensitive enough to pick up the pulses from the prop blades passing by, and, in some conditions, the shadow of the blade. If you run across the original Fromeco version (with a "push-to-read" switch - which sounds like a good idea but is irritating in practice), modify it per this thread:

http://www.clstunt.com/htdocs/dc/dcboard.php?az=show_topic&forum=103&topic_id=194150&mesg_id=194150&listing_type=search

   No offense to anyone who has another one, but this type of tach, going back to the original TNC - still by far the best - is the only one I have seen work reliably and consistently in all conditions.

    Brett

[BillP]

I still have the Tower tach I bought in the early 1990s and it has calibrated as supposed to on light bulbs. I actually pointed it through the windshield at the prop of my full size plane and it read the same as the plane tach, so I figured it was pretty accurate...that was at approx 3' away.  The clear lens of the sensor fell off right after I got it but it didn't make a difference all these years.  Other than needing watch batts it has served well...until yesterday. Two week ago I changed the batts out (from a $4 card at Harbor Freight) and checked it against the lights. Everything was ok (3600) so I put it away. Yesterday I pulled it out to use and found the switch was still on and the new batts completely dead. I just installed another $4 set of batts and checked it against the bulb again. Now it starts up at 4200 rpms and takes 2-3 minutes to settle down to 3700 (supposed to be 3600 +- 100).  It jumps around and finally settles down but never did this before, so I guess it got fried when I left the switch on. I going to buy another one, probably a $24 Hobbico because the LHS sells them, and see how it does. 

bp