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Help!- Heefmaf PPT Dialing Pops and Ringing Problems

Started by Kenton K, January 18, 2014, 08:50:56 PM

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Kenton K

Just got a cool Heefmaf PPT Model 1955, the type that looks like a batmobile. I got it off eBay and it came with a small chip. The seller was nice enough to refund the $ and let me keep the phone.  :-*

Anyways, I cleaned up the phone and it dials, receives, and transmits. However whenever I dial or hang up, I hear super loud pops. I also cant get it to ring, but I suspect that has to do with different ringing voltage.

Here is the diagram I used:
 
[url]http://telephonecollectors.info/index.php/browse/wiring-diagrams/all-wiring-diagrams/doc_details/1134-heemaf-type1955-tafel-at[/

Any ideas?

Matilo Telephones

Hello Kenton,

Very nice find. Nice price too!

How did you hook it up?

Do the pops correspond to the pulses of the dial, when dialing?

Can you provide a closup of the hookswitch?

Do you hear the ringing signal over the transmitter when the handset is on the Phone?
Groeten,

Arwin

Check out my telephone website: http://www.matilo.eu/?lang=en

And I am on facebook too: www.facebook.com/matilosvintagetelephones

Matilo Telephones

By the way, the wiring in the 2nd pic seems to be correct.
Groeten,

Arwin

Check out my telephone website: http://www.matilo.eu/?lang=en

And I am on facebook too: www.facebook.com/matilosvintagetelephones

dsk

Hi
Nice phone,
-Regarding the ringer:
It should ring well when connected to North American systems.  The yellow and blue wires should be connected together to one line. (By theory tip but that's less important)  The Red one are for the other wire (Ring).
The green one have no real function today, but will be equal to what was used on ground start lines. In Europe it was used on some exchanges as you use hook flash.  If you connect the wire to the tip, it will short the line when you press the white button.

-Regarding the loud clicks, I'm less sure.  It was quite common on these, at least the oldest one, to generate a loud click when replacing the handset, and an almost that loud click when the dial returns to rest position, other clicks should not be that loud. If the noise cancelling device at the picture are missing (symbol of 2 diodes) or not working, it should be replaced.
2 rectifier diodes doe the job, or a similar device from any telephone. Typical receiver element from e.g. a W.E. 500 are soldered on the rear of the receiver.


dsk

dsk

I forgot, The Ringer load will probably be about 2 REN's or equal to 2 traditional phones like W.E. 500. You may try to reduce this by putting in a 1 microfarad capacitor, or a 3-4 kilo-ohms resistor between yellow and blue wires instead of connecting them together. but make it work without, and try later if you need.

dsk


G-Man

I have to confess that I find it difficult to decipher the European schematic provided for this telephone set.

However, it appears that click suppression was provided by the device represented by back-to-back diodes but as DSK has pointed out a WECo 44A or an equivalent varistor would be worthwhile to install.

I also suspect that the hookswitch has a contact pair that is supposed to briefly short the receiver as the handset is removed from the cradle or the plunger buttons are depressed. And of course the dial should have muting contacts for the receiver as well. Simply cleaning and adjusting these contacts may remedy the problem.

Perhaps popular1 or someone else with better eyesight than I can identify the contacts.

dsk

Let us try to explain the schematics.  :)
R= Receiver, T=Transmitter
The hooksw. are simple, h2 connects/disconnects the voice path.
h1 disconnects the ringer when offhook, and forms a filter for the dial pulses by using the capacitor and a 600 ohms resistor. (not important)
The dial shorts the complete voice circuit when the dial are out of rest position. (No extra contacts for the receiver.)
at= ground start contact, (as used in N.America)

If you look at the network, you may find equal circuits in some older AE phones (Triad circuit)

dsk

G-Man

Thanks DSK your annotations and translations make the schematic easier to understand since some of the symbols are different than those used in North American telephony.

Interesting that both the dial and hookswitch were manufactured without the additional contacts to suppress loud clicks in the receiver. Even Kellogg's Triad circuit used hookswitches and dials with additional contacts to protect annoying and possibly damaging clicks.

Matilo Telephones

Guys, not sure if I understand you correctly but the diagram is incomplete. It doesn't show all the components and switches. Here is a pic of the complete one.

There is a diode across the receiver coil. Also the handset disconnects when the dial is activated. It normally doesn't click at all or only faintly.

Perhaps the diode is damaged or loose, but my first guess is what G-man said. Check for the hookswitch and the timing of it. There is a specific sequence for the switches to go on and off. Also the switching in the dial might be off, perhaps resulting in not disconnecting the handset.

If it is improperly connected to the line (asuming the phone is not malfunctioning) it results in a short and the phone not working at all. Or it rings 2 or 3 times and it hangs up when recieving calls and in case of an outgoing call it has very soft reception and transmitting.

CLicking and not ringing is not a symptom a wrong connection to the telephone line.
Groeten,

Arwin

Check out my telephone website: http://www.matilo.eu/?lang=en

And I am on facebook too: www.facebook.com/matilosvintagetelephones

Contempra

There's no wire on the scew number 8....and the Kenton's phone has 2 wires conencted on it.....I'm not good on this kind of phone but I observe the shematic..and I saw that this screw has no wire...Just a comment from a beginner :)

LarryInMichigan

My Heemaf phone also makes load clicking noises when the hook switch closes and when the dial is moved.  I never really paid much attention to it.

Larry

dsk

I cant really see what components missing, but I don't have the Heefmaf myselves.
When you have got it ringing and working OK else, it would be interesting to hear about the clicks, I may guess it is as Larry says.
I did never pay attention to those sounds before I got some American phones to play with. They are just better on those ant click and anti tinkling solutions.  ;D

dsk

twocvbloke

Quote from: dsk on January 19, 2014, 03:42:37 AMIf the noise cancelling device at the picture are missing (symbol of 2 diodes) or not working, it should be replaced.
2 rectifier diodes doe the job, or a similar device from any telephone. Typical receiver element from e.g. a W.E. 500 are soldered on the rear of the receiver.

GPO 700-type phones have a rectifier (Rectifier No. 205) wired across the receiver terminals inside the phone, this rectifier is simply composed of a pair of diodes wired back to back in parallel (so the anode of one is connected to the cathode of the other) and was fitted to reduce the loud pops (or "Acoustic shock" as they called it) in the receiver from operating the hookswitch... :)

I don't really get how it works, but it does, I tested it in one of my phones, without it the pops are very loud, but with, they're still here, but much more quiet and less of a nuisance... :)

Kenton K

OK guys. Here are some more detailed photos. There is the hookswitch, and included diagram pictures.

I also found that my heefmaf  has slightly different components than the TCI diagram I used. In my phone, there is no varistor, or the two diodes anywhere. The is reflected on the wiring diagram on the telephone itself, so I don't think it had a varistor originally.

Also, my dial has an additional switch. But the additional switch is not used (two contacts coupled).

The phone only pops when you start spinning, it does not pulse. And the ringer is working, something was stuck between the clappers. So 1 problem solved!

KK


dsk

Great pictures!  :)
If you are going to use this phone regularly, I will recommend to put in a varistor or a pair of rectifier diodes.
The screw no 7 looks like a 1 in your upper corner diagram.
I guess you have a dial problem, the terminals seems to be wired correct. You could try to just remove the green and blue, and tape them. (You will get lots of high clicks if it works, but it may dial.) When you have sorted out how to repair/tune the dial, you could try to move the blue wire to 7, but not before everything else works.  If you could take some pictures of the dial contacts in rest position, and when dial is rotated to e.g. no 5. and when you let the dial slowly go back to the pulse contacts are open.

dsk