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$2 Clock Kit

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  • TorTor Posts: 2,010
    DAB country here. FM has been switched off. Big energy-sucking block of a radio. No sleek ultra cheap running-for-months radios anymore. AC, or charge every day. It's like going sixty years back in time. Worse.
  • ercoerco Posts: 20,244
    edited 2018-05-16 21:34
    So you guys must replace all of your car radios too? Who thought THAT was progress?
  • DAB, is there for minimise frequency bandwith.
    Shrinking frequency, not energy.

    Everybody wants everything wireless.... WIFI, MOBILE, REMOTE, 3G,4G,5G, Sat TV, GPS ....

    I can confirm the quality is much better than FM.
    I listen already for several years, even my car has standard BAD
    It is an European decision.
  • Ltech wrote: »
    DAB, is there for minimise frequency bandwith.
    Shrinking frequency, not energy.
    Follow the money!
    Ltech wrote: »
    Everybody wants everything wireless.... WIFI, MOBILE, REMOTE, 3G,4G,5G, Sat TV, GPS ....
    FM is not wireless?
    Ltech wrote: »
    I can confirm the quality is much better than FM.
    I want it small and I want it energy efficient and I definitely do not need an audio quality outdoors and in the car that is by dimensions better than my ears!
  • K2K2 Posts: 691
    erco wrote: »
    NOW... Real men build their own $2 FM receivers! :):):)
    https://www.ebay.com/itm/192119861885]
    Couldn't agree more, ercoman. I liked that kit so much I bought two more.

    FM_RX.jpg
    1976 x 1482 - 304K
  • ...or one I²C tuner per ear?

    —▷ https://www.ebay.com/itm/253112898517
  • K2K2 Posts: 691
    Couldn't pass up the opportunity to mention two more great kits. Of all the FM transmitter boards and modules that are available, these are my two favorite. They are closely related to each other. Main difference is that one uses a variable capacitor for tuning. The other uses a slug-tuned inductor. The former board also has a pot to adjust modulation level. The latter has a preset level that is very well chosen.

    Both of these boards switch between the onboard microphone and a 3.5mm aux in port. I love that feature because more often than not I'm transmitting data, not voice or music.

    They are more stable than most wireless mic circuits because there are three separate stages: audio amplifier, rf oscillator, and rf amplifier. Also, the last two stages use real rf transistors, not 2N3904 or PN2222.

    https://www.ebay.com/itm/FM-Wireless-Microphone-DIY-Kits-Suites-FM-Radio-Transmitter-1-5-9V-76-108MHz/332263126483?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649

    https://www.ebay.com/itm/DIY-Kit-88-108MHz-FM-Transmitter-Frequency-Modulation-Wireless-Microphone-Suit/222791624095?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649

    FM_TX.jpg
    1453 x 1040 - 260K
  • jmgjmg Posts: 15,140
    David Betz wrote: »
    I have to say that the people who sell this $2 clock kit are very responsive to support requests. As I mentioned earlier, they sent me the source code for the clock and they sent me a new MCU chip when my clock didn't work. After the new MCU chip didn't help the problem they offered to send me a new kit or refund my money. I'm not sure what went wrong with my kit assembly but they are certainly trying to resolve my problem. That's pretty amazing for a $2 kit!

    Did you ask them if they tested the MCU they sent ?
    Can you read those parts yet ?

    Looks like you can read without needing 12V : just RST=H, and the internal counter feeds bytes out on P1, from 0000, & pulse Xtal pin, to advance.
    I think secured reads 0xff, so the very first byte should be < 0xff, eg 0x01 0x1D 0xff..

    Programming is only slightly more complex : RST=12V and Erase pulse of 10ms, then PGM/Busy handshake as you apply bytes & pulse Xtal
  • Heater.Heater. Posts: 21,230
    edited 2018-05-16 21:20
    erco,
    Wow, never heard of DAB before!
    What?

    How amazingly isolated from the rest of the world America is.

    Digital Audio Broadcasting has been around for ages. Now it has gotten so bad that there is no traditional AM or FM broadcasting in Norway. Drive there and your car radio has nothing to receive.

    No, they want you to buy a DAB receiver.

    Thing is, cellular coverage is so good everywhere, hence internet access, that who needs an AM/FM/DAB radio anymore? Just play the tunes you want from the net anyway.







  • In the UK, DAB broadcasts (not DAB+ because we were early adopters) are worse quality than FM - and sometimes in mono so that they can cram even more useless stations into the available bandwidth.

    Besides the problem of the receivers being much more power hungry - so battery powered ones eat the batteries in a day or so - there is also an unpredictable delay which means that the time 'pips' are no longer an accurate way of setting clocks. If you have an FM radio and a DAB one both receiving the same station (FM hasn't been switched off here, yet) then the DAB one is usually a couple of seconds behind the FM one, but sometimes more - maybe it even varies from one receiver to another depending on how their decoders are programmed and how fast their processors are.
  • ercoerco Posts: 20,244
    Nice work, K2! You're doin' this hoarder proud!
  • jmg wrote: »
    David Betz wrote: »
    I have to say that the people who sell this $2 clock kit are very responsive to support requests. As I mentioned earlier, they sent me the source code for the clock and they sent me a new MCU chip when my clock didn't work. After the new MCU chip didn't help the problem they offered to send me a new kit or refund my money. I'm not sure what went wrong with my kit assembly but they are certainly trying to resolve my problem. That's pretty amazing for a $2 kit!

    Did you ask them if they tested the MCU they sent ?
    Can you read those parts yet ?

    Looks like you can read without needing 12V : just RST=H, and the internal counter feeds bytes out on P1, from 0000, & pulse Xtal pin, to advance.
    I think secured reads 0xff, so the very first byte should be < 0xff, eg 0x01 0x1D 0xff..

    Programming is only slightly more complex : RST=12V and Erase pulse of 10ms, then PGM/Busy handshake as you apply bytes & pulse Xtal
    I haven't been able to find any software that works with the programmer that I purchased. I have 10 spare MCU chips though so if I can ever put together a programmer+software I should be able to experiment with the source code they sent me.

  • ercoerco Posts: 20,244
    Did it go unnoticed what DAB is backwards?
  • jmgjmg Posts: 15,140
    edited 2018-05-16 22:26
    David Betz wrote: »
    I haven't been able to find any software that works with the programmer that I purchased. I have 10 spare MCU chips though so if I can ever put together a programmer+software I should be able to experiment with the source code they sent me.
    Maybe you can port something like this to run on a Prop ?
    Ardunio 89C2051 programmer

    AT89C2051 specs 5V +/-10% during pgm, but looks to have TTL levels on all pins, and light pullups, except for RST and XTAL1, so should P1 connect ok ?

  • jmg wrote: »
    David Betz wrote: »
    I haven't been able to find any software that works with the programmer that I purchased. I have 10 spare MCU chips though so if I can ever put together a programmer+software I should be able to experiment with the source code they sent me.
    Maybe you can port something like this to run on a Prop ?
    Ardunio 89C2051 programmer

    AT89C2051 specs 5V +/-10% during pgm, but looks to have TTL levels on all pins, and light pullups, except for RST and XTAL1, so should P1 connect ok ?
    I'm sure that would work but I was trying to avoid having to build my own programmer.

  • kwinnkwinn Posts: 8,697
    erco wrote: »
    Did it go unnoticed what DAB is backwards?

    No.
  • K2K2 Posts: 691
    kwinn wrote: »
    erco wrote: »
    Did it go unnoticed what DAB is backwards?

    No.
    This is particularly funny coming from a Canadian. :-)

    Note To Forum Police: This is not a put-down of Canadians! What you may not know is that Canada had a 10-year experiment with DAB. kwinn ought to know better than most what DAB spells backwards. Sheesh!

  • Explanation received.
  • kwinnkwinn Posts: 8,697
    K2 wrote: »
    kwinn wrote: »
    erco wrote: »
    Did it go unnoticed what DAB is backwards?

    No.
    This is particularly funny coming from a Canadian. :-)

    Note To Forum Police: This is not a put-down of Canadians! What you may not know is that Canada had a 10-year experiment with DAB. kwinn ought to know better than most what DAB spells backwards. Sheesh!

    I did spot the backward spelling in the original post and passed it off as the typical typo that is fairly common on this or any forum. When I read your post I was not offended, only curious to know why it would be particularly funny for a Canadian, so thank you for clearing that up. Obviously I did not pay much attention (actually none at all) to the DAB experiment.
  • Good Day/Evening! I've bought the C51 6 bit clock kit. It seems to be a straight forward project. My one question if anyone could help me Is; My PC board for this kit looks like it's a new production board. It kind of resembles the older boards for this kit. My question is this; every part is shown on the board with the proper mounting position, except for the voltage regulator. There is no indication on the silk screened board to inform the builder which way this part mounts? Everything else mounted on the board indicates it's correct position except the VR. Can anyone inform me which way this part is mounted in the board? Does the flat side of the part face the top of the board, facing J1 or is it mounted backwards facing J2 it looks like a NPN transistor. Any help would be appreciated. My thanks in advance and have a great day every one!
  • kwinnkwinn Posts: 8,697
    If your board matches this image then the flat area of the regulator faces the top of the board as outlined in the attached image.
    1920 x 1080 - 342K
  • ercoerco Posts: 20,244
    edited 2019-10-23 15:28
    Welcome, ehjohnny! Always wise to ask. When in doubt, Google the VR for the pinout and do some sleuthing on the PCB. The ground pin will go to the negative power connection. The input will go to the positive power connection and the output will fan out towards the IC and other components.

    As always, tune for minimum smoke. :)
  • Thank you very much for the info everyone. It was easy to orient the part once I had the pin out and finding the + power connection. Thanks for the welcome! I will take some time to snoop around come the weekend.

    Cheers and thanks to all who answered!

    Johnny
  • ceptimusceptimus Posts: 135
    edited 2021-01-21 17:49
    Someone built one of my Arduino-based AT89C2051 programming devices, and found a bug in my code. It's been ages since I did one of these, and I couldn't find my old clock to test the bug. I built a fresh one up from a kit I had. One of the red LEDs was missing, so I substituted some yellow ones. Also missing were a couple of capacitors - but I had some in stock.

    Anyway, that bug is now fixed (no doubt there are more!)

    I've attached the .hex file for the AT89C2051. This one has clock, alarm, stopwatch, and countdown timer modes. I'm looking at writing some fresh, simpler C code for the free SDCC (Small Device C Compiler). Previously I used Keil, but that's commercial and the free Keil version has some pretty severe limitations.
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