Author Topic: BK 1045 DIY substitution (Read 1192 times)

Sigmaz · « **on:** February 14, 2018, 09:51:25 PM »

The rarity and prices of these test devices have forced me to build my own.

It’s still a work in progress but it’s coming along.

Right now it’ll do ring test, receiver test, Pulse and DTMF decode and will soon also handle TX level test and polarity reversal.

https://youtu.be/TETn2Nm0N3w

AE_Collector · « **Reply #1 on:** February 14, 2018, 10:20:22 PM »

Good project!

I don’t think the BK1045 analyzes Make/Break ratio or Dial Speed, it just counts pulses. Not certain about the BK1050. These seem like fairly basic things that should be included in a telephone tester for hobbyists and old phone refurbishers.

Terry

Sigmaz · « **Reply #2 on:** February 14, 2018, 10:32:14 PM »

That is certainly something that can be analyzed.
The code watches the rise and fall of the switchhook to detect pulse events.
It can certainly report back the values of the timers quite easily

Pourme · « **Reply #3 on:** February 15, 2018, 05:39:22 AM »

Nice...Fortunate for you, you can build that device. Enjoyed the video!

Benny

twocvbloke · « **Reply #4 on:** February 15, 2018, 07:05:26 AM »

If you want to put it into something to make it look like a piece of test equipment, Banggood have these project boxes with carry handles on sale:

https://www.banggood.com/Electronic-Plastic-Shell-Cartridge-Handle-Project-Case-Desk-Instrument-200x175x70mm-p-1035473.html?cur_warehouse=CN

And with a little more fettling of your code, you could probably integrate a small LCD display in there (whether it's a video display or a basic 20x2 LCD) to display the functions...

Sigmaz · « **Reply #5 on:** February 15, 2018, 07:14:05 AM »

Quote from: twocvbloke on February 15, 2018, 07:05:26 AM

If you want to put it into something to make it look like a piece of test equipment, Banggood have these project boxes with carry handles on sale:

https://www.banggood.com/Electronic-Plastic-Shell-Cartridge-Handle-Project-Case-Desk-Instrument-200x175x70mm-p-1035473.html?cur_warehouse=CN

And with a little more fettling of your code, you could probably integrate a small LCD display in there (whether it's a video display or a basic 20x2 LCD) to display the functions...

Thanks for the link! That’s exactly what I was planning on locating for it.

Yeah, it’s definetly getting a 4x20 LCD display for showing the data.
I have a graphical LCD and an OLED display too but I don’t want to waste them on this project besides the available program space would run short with the size of the support libraries.
I will free a ton of space once I ditch the Dialtone PCM data and just generate a single tone simulation.
TMI, sorry I get all geeky sometimes.

twocvbloke · « **Reply #6 on:** February 15, 2018, 09:05:05 AM »

No probs, that box is tempting for me to buy, no idea what I'd use it for, I'm just like a magpie for such things...

dsk · « **Reply #7 on:** February 15, 2018, 12:29:10 PM »

Really nice!

Now you have the possibility to put out real dial data;
the pps rate,
The average, max and min break percentage.
How close the DTMF tones are to ideal. (I have no idea about whats OK or not for DTMF) Some dtmf pads may come out of tuning.
How high the REN load are? (Impedance at 20, 25, and 50-60 HZ.)

dsk

Sigmaz · « **Reply #8 on:** February 16, 2018, 11:11:39 PM »

Quote from: dsk on February 15, 2018, 12:29:10 PM

Really nice!

Now you have the possibility to put out real dial data;
the pps rate,
The average, max and min break percentage.
How close the DTMF tones are to ideal. (I have no idea about whats OK or not for DTMF) Some dtmf pads may come out of tuning.
How high the REN load are? (Impedance at 20, 25, and 50-60 HZ.)

dsk

I can easily get the pulse rate and make/break ratio data pretty easily because of the way the pulse detect function watches the switchhook.

The DTMF tuning is a little harder.

The device isn’t using any external hardware to decode the tones in fact it’s sampling the audio stream via analog pin 0 and through the magic of a modified Goertzel algorithm implementation its able to pick out the 8 specific frequencies that make up 0-9,#,*,A-D.

To identify any shift from the expected would require a much more elaborate setup.

compubit · « **Reply #9 on:** February 16, 2018, 11:38:54 PM »

Great project! When I started reading this thread (before I went to the video), I was thinking this would be a great RaspberryPi project, especially if you tied it with a touchscreen or LCD display.

Arduino makes perfect sense too - although I'm not as familiar with them (vs, Pi).

I also liked the Rotary to DTMF converted for your 1C1.

Jim

Sigmaz · « **Reply #10 on:** February 17, 2018, 12:05:18 AM »

I appreciate the compliments.

Feel free to browse my Github. Perhaps I have done something else you can find useful.

Then again, it’s a pretty messy place..
The code for this project is there too but of course it’s a work in progress..

https://github.com/SigmazGFX

dsk · « **Reply #11 on:** February 17, 2018, 02:04:48 AM »

Great, I do the analyzing of my dials completely manual by studying the graphical presentation of the dial pulses, this may be much faster. I guess I have to look if I could learn some C++ on my older days. (54)

Keep on the good work! and pleas continue with telling us.
For me the pulse dialing analyses is the most important part of this project. Making the pulse to tone converter is another nice thing to learn. Especially if it is possible to make it as tolerant as the XLink adapter who understands pretty un-tuned dials.
Thank you!

Sigmaz · « **Reply #12 on:** February 19, 2018, 01:32:16 PM »

I'm working a little on it today.
Building in the pulse speed reporting now.

Testing with a crap "Curtis" 2 line desk phone and My Harris TS-44 "Butt Set"

Both come in at ~18 PPS. I was a little surprised to see this. I kept checking my code to see where I messed up assuming the max was ~10 PPS

I remembered that I knew that newer switching systems with digit registers accepted faster pulse rates. I wasn't aware that it was this much higher.
(of course I checked the intertubes and now I know... ) lol

Oh.. and yes, I have a new display for the finished project.
This one is a test display that gets kicked around from build to build.

AE_Collector · « **Reply #13 on:** February 19, 2018, 10:39:45 PM »

Very ~~scoop~~ Good!! Keep up the good work.

Terry

twocvbloke · « **Reply #14 on:** February 20, 2018, 03:35:15 AM »

Looks good, just need the project box to mount it all inside...

If your visit to the Classic Rotary Phones Forum was enjoyable or helpful, you may tell us by making a small donation. The donation can be made safely via PayPal and will help to off-set the costs of the Forum operation. Thank you!