Kundo electro-mechanical clock help needed

[leeinv66]

It seems that the movement from the quartz clock could
have been made to drive the coil in the original with very
little work.
I would guess the original and the quartz one were quite
similar.
Tinker Dwight

You could be right Tinker, I had the same thought. But, being far from competent with electronics, I went with the parts I already knew worked.

[Mike Phelan]

Peter

So, you're using the quartz to actually drive the coil? I'm interested. Shame you're on the opposite side of my planet!

Dwight

I've only heard of those meters but never seen them here; I have a military spec Avo 8 that I got as a prezzie when I left my first job in 1967 to move up north, and as it's been calibrated a few times, trust it implicitly. Lead reversal is my usual transistor test method. There's another Avo 8 that lives in the workshop outside, plus about five cheap £5 digitals that actually have a transistor/diode test function.
If I need to go as far as hfE testing, I have a Taylor instrument from the 1950's when transistors cost a small fortune then.

Apologies to moderators for wandering a bit O/T, but electronics is becoming nearer and nearer to horology; the former was my working life, the latter my hobby.

[Tinker Dwight]

Hi
I believe the quartz had a separate circuit to swing
a pendulum that is independant from the quartz time keeping.
It is just to make the pendulum effect.
I've not traced one down but think it is similar to the
original Kundo.
Next time I see one with the pendulum, at a garage sale,
I'll have to rip one apart and see if it makes a good drive
for one of these clocks. I don't see why it wouldn't.
Tinker Dwight

[harold bain]

Tinker, Timesavers sells a unit that just swings a pendulum, meant to wrap around your typical square quartz movement. Takes a separate AA battery. Part # 23552.
Not sure how it would keep in sync with a Kundo pendulum, but maybe it doesn't matter.

[Tinker Dwight]

Hi Harold
It looks like it works on the same principle.
There is a magnet on the end of the hanger
and a coil in the base.
I would think it is basically the same.
Dwight

[Scottie-TX]

Kudos Pee-Tah!
They're similar to KUNDOS.
I'da never thunk ta do that. Congrats!

[redwire]

wow I like that I think you are on to something here not sure if this will work on my lantern as the coil and movement are mounted on clear plexiglass.
I think i have one of those quartz movements around here somewhere.I might give this a try...............thanks tom

[redwire]

hello mike did I understand correct that the original tf65 transistors are avalable in your country? if so are they costly and could you help us out over here ?
I like peter's idea and I will try it if all else fails............thanks TOM

[technitype]

You have it reversed...N is the "cathode", and P is the "anode".

To forward bias a PNP base-emitter junction, the negative lead goes to the BASE lead, and the positive lead goes to the EMITTER lead. A transistor must be forward biased to turn on.

Something else you need to remember...and it is bloody important!...the current through a semiconductor junction MUST BE LIMITED!!!

The coils have enough DC resistance to limit the current through the transistor junctions to a safe value, but if you connect the battery voltage DIRECTLY across the transistor junctions, it will blow them out! As an example: if the (-) terminal of the 1.5 volt battery is connected directly to the base lead of a PNP transistor (whether silicon OR germanium) AND if the (+) terminal of the same 1.5 volt battery is connected directly to the emitter lead, the transistor is toast!!! In electronics tech lingo, this is called "excessive forward bias", and the result is called a "catastropic failure".

Most digital multimeters have a "diode" function built in. This may be used to safely test the transistor junctions.

[technitype]

Using the circuit from a quartz clock to drive the coils is an interesting thought- but a quartz clock ticks at a one-second rate, and I though I read somewhere that these Kundo clock tick at a THREE-SECOND rate?

These two frequencies are incompatible.

[harold bain]

Yeah, I figured that may be a problem, considering on these pendulum drivers, it doesn't matter what the beat per minute is, as the pendulum is only for decoration. However, since all that is needed is a pulse to maintain pendulum oscillation, I do wonder if one of these might be able to be tuned in somehow to the beat needed for a Kundo? Would an extra, unneeded two pulses be a problem, as long as there is a pulse there when needed? Anyone tried this since last summer?

[technitype]

And I might add...stay away from using the Rx1 or Rx10 scales on the multimeter. These scales will very likely allow too much current to flow through the transistor junction(s), causing damage to the transistor. Use the Rx100 scale.

[technitype]

"If it won't "tick",
let me "tock" to it"

...well, it's about time! (snucker-snucker-snucker!)

[technitype]

[QUOTE=harold bain;636378]Yeah, I figured that may be a problem, considering on these pendulum drivers, it doesn't matter what the beat per minute is, as the pendulum is only for decoration. QUOTE]

? That's news to ME- I thought the pendulum rate was what ran the clock...

Even so, if you input a one cycle per second pulse into the pendulum coil, the pendulum has to swing at a one second rate, or it can't keep up with the input pulses.

[technitype]

AW...you've got KITTY!