I got the master clock and the slave clock from E-bay (not from the same listing) I thought about the fuses thing but if there is any I can't find them.
I programed the master clock with code "17" from the users manual. So I belive that should be ok.
ok I was able to do the test....to a point...I found the T1 and T2..but....Where is the Negative DC common of my power supply?

also....from the print out on the door I seen that the transformer is only a 12VAC one.....did I miss something on this?


(1) Do you have a copy of the Lathem LTR2-384 operator's manual?
Yes

(2) Which version of the EPROM is in your master unit: the F-9 version, or the G-9 version. (The manual describes how to determine that.)
F-9 (Standard)
(3) Please confirm that you can measure 24v DC from your power supply. If so, let's go to step (4). If not, then please check for a blown fuse in the 24v line from the power supply. If no fuse, or no blown fuse, we may be looking at a dead power supply.
Power Supply is only 12V....not sure here on what 2 do. No fuse. ...But the clock has life (display is alive)

(4) From looking at the numerous wiring diagrams in the Lathem manual for the various supported brands and models of slaves, it seems that master relay SK1 looks after the regular minute pulses, and master relay SK2 handles the correction pulses.

Relay SK1 is manifest as terminals 1 and 2 on the terminal block, which I call T1 and T2.

With the Lathem programmed correctly by you, and 24v DC positive connected by you to T1 then with your voltmeter connected between T2 and the negative DC common of your power supply you should be seeing a 24v pulse every minute .

Back to the 12V thing again...

post error Moved all to one post (looks better)

It's hard to answer that without a clear still photo of the power supply so I can see the wiring in detail, however if it's an AC output ...



If your low voltage supply only outputs 12v AC, then it won't run that AR-3. You would need to source a 24v DC supply elsewhere.



As above re voltage.

Okay, so you need to get yourself a 24v DC supply to replace the 12v AC one, or find a slave clock that runs on 12v AC.

In the meantime, if the master is indeed running properly, then you should be hearing the SK1 relay click each minute, and an ohm meter placed between T1 and T2 ought to show open circuit for 59 seconds and then quickly jump to zero ohms and back to open circuit when the pulse click occurs (best to use an analog meter for that as the pulse may be too quick for a digital meter to respond to). You need to have nothing else connected to T1 and T2 during that test.

Thanks GTC for taking the time to post all the pictures and schematics. Yes the schematics make no sense at all. One would think by now they would have released a corrected version.
I’ve been having to go to school for my work so it takes up my time and will for awhile. Continuing Education Credits thing. So I don’t lose part of my salary, as if I can live on it now..

The 12vac xfrmr runs the Lathem time clock. Do you only have the little one? Just a little master clock with a black face, say maybe 14” long and 6” tall? Takes a brass key to open it over on the right? Then you need an outboard DC supply and you will have to input it into the relay contacts to run your slave.


-Charlie

go to kensclockclinic.com to get yourself an impulser that will run your slave clock and forget about the master.

Ibm/Simplex are much simpler to understand and figure out.

If you play his YouTube video (see post #6) you can see his setup.

The Lathem is self powered. Underneath the master unit he has an outboard/auxiliary power supply labeled on its door as "PSB 2412" which I note also says 2 wire system (so it's not intended for AR-3 slaves anyway) and which shows the slave/secondary outputs as AC. I'm thinking that power supply may have been used for bell circuits.

He needs to replace that whole PSB 2412 box with a straightforward 24v DC supply.

But before that, I suggest that he needs to ascertain if the Lathem is working correctly (i.e. outputting the correct pulses) -- which can be done independently of the outboard supply.

Yes I hear the click of the relay but nothing is showing the on meter and yes mine is analog type....looks like my master is dead?


I will do more testing

Yes I have the little one with the black face and the key on the right..
Looks like I do need more....*sighs*



What setting should the meter be on? mabey I am not useing the right setting?????

I had the same master clock at my local Highschool and I thought it would be nead to have the same one at home....I will keep what you said in mind.

You need to be using Ohms x 1.

If you can hear clicking on the minute then that seems to indicate that the minute pulses are being generated, so that's encouraging.

As well as using ohms x 1, you need to have identified terminals 1 and 2 of the SK1 relay.

Is there somebody local (buddy, relative, etc) who's savvy with electrical work who can give you a hand with this stuff?

I think you are right GTC… only plausible explanation for having the 24vac supply, AC travels so on a several hundred foot run still would have good voltage to ring the bells.
Only other thing would be that Lathem ran 24VAC clocks when it was fitted. Too bad his slave does not have a motor… would be easy to retro to AC.

I did build a pulser in 1984 when I started at the school district, they are not that hard to make, but defeats Anthony’s purpose of why he wants that Lathem.

Ok I’ve got the video paused, it looks like on that circuit board to the left that I count 3 diodes? And 8A@ 24v on the xfrmr? The orange wire is in the way.
I also hear the relay pick but don’t see anything connected to the terminal strips other than 120vac. There is no interconnect. The upper relays are going to be the one’s that do the work. Those 2 lower one’s in the can are to expand the signal circuits I think. See it’s only got 2 bell circuits shown on the front panel. They may have expanded that master clock as the school grew in size or something. I’m wondering if 2 of those diodes could be a ½ wave to derive 24vdc?

-Charlie

Yes, I noticed that the transformer says 12v and 24v, presumably you get 24v AC by series connection and 12v AC by parallel connection of the secondary.



My sound card is not working at the moment so I can't hear the audio track.

That auxiliary power supply is a bit of a mystery to me. The circuit schematic on the inside of the door does not seem to correlate with the PCB -- for instance I don't see the power transistor in the schematic -- but then the video is a a bit wobbly and I couldn't pause it well enough to get a good clear image.

And those relays on the PCB are also a mystery other than as you say to increase the switching capability for bells, etc.

Thinking about it, you may be right about later expansion, so that particular PCB may not relate to the original diagram in the inside of the door?

But, yes, there are diodes and one would expect a DC output somewhere on the PCB's terminal block.

I'd love to run a meter across that PCB and find out what's actually going on there.

Meanwhile, it seems from this distance that the master unit is operating, so it's matter of getting a suitable 24v DC supply one way or another for his AR-3 and sorting out the correct terminals on the master blocks for SK1 and SK2.

Hopefully, TonSpa can get the correct terminals determined with his ohmmeter.

Okay, now that I have my PC working properly again (i.e. out of Safe Mode) I can hear the audio track of that YouTube clip and I can also get high resolution vision.

Yes, you can clearly hear the minute relay operating, so it should be quite easy to see/feel it operating too and thus follow the copper tracks showing through the circuit board beneath the relay in question to the terminal block below it and thereby determine which are the ones that are used to switch the minute pulse to the slaves, that is those that go close closed circuit for the duration of the minute hand pulse.

Having done that, we're on the way to getting this little system going!

No there is not anyone (My Dad has been helping) Everyone here thinks I am crazy even trying this. They tell me to junk it all and get a battery clock easy that way they say........sighs...

I called a clock repair shop in the city (30 miles) from me. And they told me that they can't do anything for clocks that I have. They told me that I should call the company that made it.

I will do more testing...OH Guys Do you want me to take some pictures of the system? I seen you are useing the video for pics? I can do that if it will help any.
thanks for all the help!!!!!

Forget the naysayers. Once you get it working you can have the last laugh.

I like the look of the master and the slave and I think it's a worthwhile pursuit to get the system up and running.

I'd like to have a go at it myself, but I'm about 10,000 miles and an ocean away!

Is there a vintage radio club in your state/region? If so, I'm sure guys in it would be happy help you out with the testing. In my experience, old electronics technicians love a challenge of any sort and the circuitry involved isn't very complicated.



I guess I'm not surprised. The gear is a few decades old and it's also sort of specialized. It's like trying to get old radios fixed. The current generation of repairers (if any!) have no idea about them, nor do they care, so we fix 'em ourselves, with help as necessary.



I think the video is sufficient for the time being. (I had trouble with it earlier because a virus forced me to use Windows Safe Mode and the video driver in that mode is very low quality. Now that I've gotten rid of the damn virus I can view the clip properly.)

As I said above, the relay that is clicking away each minute ought to be obvious -- that is, you should be able to see it pulsing through its transparent plastic cover and feel it, too. If you follow the circuit board tracks beneath that particular relay, you should be able to work out which terminals are involved (i.e. T1 and T2 in my parlance), and verify that by the ohmmeter test described earlier. Disconnect any wires attached to the master clock relay terminal blocks first. This test needs to be done on bare terminals. (And stay well away from mains power at the right hand end of the master.)

Do that first and get back to us when you've got a result. A good clear still photo showing both the relay and the terminals that you have identified as the minute pulser (i.e. SK1) would help us confirm things.

If it's still not clear what to do, then let us know ...

I may be quiet for a bit. My Dad got hurt so I am going to be at the house for a while. He is fine. I just want to be there. I will be back on here again soon. (with his help) I want to get that master to work.

Hope your Dad gets better fast. Gotta take care of 'em.

Hope your dad recovers quickly. See you here when you both get back on the task.

I am back...If anyone still wants to try this....up 2 u guys

OH Dad is good again. he hand is all better

Good to hear all is well again.

I'll get back to you as soon as I can, and we'll get this baby operational!

.