Best Tiny Tach type

[jeffstevens763@g]

Is the cable length critical on these or can they be extended?

[Limecc]

Originally Posted by jeffstevens763@g

Is the cable length critical on these or can they be extended?

Probably by a little but the wires are extremely fine you wouldn't get any heatshrink that small. Electrically the resistance, capacitance and voltage drop would effectively be the same.

[Poly]

Originally Posted by Limecc

Probably by a little but the wires are extremely fine you wouldn't get any heatshrink that small. Electrically the resistance, capacitance and voltage drop would effectively be the same.

How small? I've seen adhesive lined shrink that does <1mm after shrinking, surprised if the insulated wire is too small as it will be very vulnerable.

Tinytach say not to extend the red wire, but extend the coax: https://www.tinytach.com/faq

I guess it's not just a simple case of DC voltage is it? My simple brain explodes when we talk impedance rather than resistance, but if there is an issue I suspect that is where the problem lies. That said, given the rather crude "wrap it round a few times" approach I am surprised it matters.

[jeffstevens763@g]

Originally Posted by Limecc

Probably by a little but the wires are extremely fine you wouldn't get any heatshrink that small. Electrically the resistance, capacitance and voltage drop would effectively be the same.

For my application I would be talking 3.5 m sounds a no goer.

[Fenlander]

Someone on PM mentioned my tach the other day so thought I'd just update. As posted above once I'd tested the boat and our load with my alternative props I had no need to see the revs under way so the tach has lived under the hood for the past year as an hour meter and been totally reliable.

At £20 or less it's worked out a good balance between the £55 proper Tiny Tach and the £7-50 cheapies which some have had fail very quickly.

Honda Lawnmower & Generator Digital Tachometer Tach & Hour Meter w/ RPM Recall | eBay

[Max...]

Originally Posted by Fenlander

Someone on PM mentioned my tach the other day so thought I'd just update. As posted above once I'd tested the boat and our load with my alternative props I had no need to see the revs under way so the tach has lived under the hood for the past year as an hour meter and been totally reliable.

At £20 or less it's worked out a good balance between the £55 proper Tiny Tach and the £7-50 cheapies which some have had fail very quickly.

Honda Lawnmower & Generator Digital Tachometer Tach & Hour Meter w/ RPM Recall | eBay

I've had two cheapies - total cr@P that lasted one or two runs at most.

[jeffstevens763@g]

i did the same bought cheap as just needed it to sort the prop failed bought one same as fenlander works a treat and still external in the wet no probs

[Fenlander]

As usual initially I fitted my favourite mini tach on the Tohatsu 9.8, the type I always say is the only one I rate as accurate.... see pic of model below. It was working when it arrived but the display was blank (at rest they should show total hours recorded showing 0.00 when new) when I next looked before I'd even run the motor with it on. They have a sealed in battery with about a five year life and I guessed it might be old stock. Unusually no satisfaction from Ebay getting it replaced/refunded but no matter... I'm frying far bigger fish at the moment.

So with nothing to lose time to lever the glued on back off. It was almost fully potted but the battery visible in a yellow plastic "pouch" and factory fixed to its terminals. Opened the pouch and broke the terminals from the battery to find it an unusual size 3v a bit bigger than a 2032. It measured 0.88v so no wonder the thing was u/s.... and it was dated 2014.

I made a rough job of inserting a new 2032 I had and building up some old thin foam scraps so when the back was replaced/glued it gave good pressure to hold the terminals to the battery.

Back in place now and working... hopefully in its under cowl protected location it might last OK as an hour and tuning meter.

[Oldman2]

Are you sure it was broken? Or did you just run out of things to take apart

[Fenlander]

Ha yes it's getting close to that stage. Have to change focus... might give the Aldi middle aisle look tomorrow for things I don't need as a distraction.