Understanding and adjusting the Smiths tacho Part 1

Поделиться
HTML-код
  • Опубликовано: 27 авг 2024

Комментарии • 102

  • @alexmstudio
    @alexmstudio 2 года назад +2

    Thank you for this clear explanation. This is one of the best RUclips videos I've seen.

  • @francescoconserva8153
    @francescoconserva8153 5 лет назад +2

    Steve, I didn’t not have a tacho to tune and I will never have; I am simply delighted in listening your explanations, as usual excellent stuff, any topic you would explain! Additionally was a nice refresh on electronics.

    • @D3Sshooter
      @D3Sshooter  5 лет назад

      Txs Francesco, you know me.... And I would say that you are not that different... we have worked along side for a long time and still do

  • @grahamcummings9917
    @grahamcummings9917 4 года назад +1

    I have a smiths tachometer identical to the one you have on my 1966 MG Midget. Your detailed video was an excellent insight into the inner workings and helped to unveil the mystery within. Thank you.

    • @D3Sshooter
      @D3Sshooter  4 года назад +1

      Happy that I could help. Thanks for the comments.

  • @RODALCO2007
    @RODALCO2007 Год назад

    Excellent video. Thanks for going into so much detail on these Smiths tacho's.

  • @marcosambento9821
    @marcosambento9821 4 года назад +3

    Excellent, detailed video! Congratulations for the full explanation!

  • @danjaynes2137
    @danjaynes2137 2 года назад +1

    Thanks for the clear and thorough overview.

  • @hecklejeckle1333
    @hecklejeckle1333 2 года назад

    I have a 67 Volvo 1800S with Smiths Tacho. Your detailed video was excellent & stepped through the different parts of the electronics and function of the circuit very well.
    Only comments is that it would have been good to explain the function of the Q2 Transistor part of the circuit in the deep dive section of your video.
    Thanks for your time, patients & thorough explanation sharing your knowledge.

  • @paulmuff9883
    @paulmuff9883 24 дня назад

    Absolutely brilliant, many thanks😀😀😀👍❤️

  • @dannymatthews8228
    @dannymatthews8228 5 лет назад +3

    Excellent video information I can and will use in the future Thank you

  • @kevinritter6276
    @kevinritter6276 4 года назад +1

    Again, thank you very much for taking the time to provide such a comprehensive response. On a separate note, I also have a Rolls Royce Silver Shadow And have replaced the points with an ignition 123 product that is out of the Netherlands. Basically, it replaces mechanical advance with an electromagnet and obviously provides a more efficient spark. I will send a RUclips video, however, it will not have the production value of the ones you produce.

  • @MGB-learning
    @MGB-learning 4 года назад +1

    Outstanding info. Thank you. From California USA.

    • @D3Sshooter
      @D3Sshooter  4 года назад

      Txs for the comments , love California, been there several times at the Van Nys valley.

  • @KWTGROUP
    @KWTGROUP 4 года назад +1

    Such a fantastic video! Well documented and explained in simple schematics. Adding the bench schematic setup would have been helpful, though. Look forward to all other videos!

  • @IngeBall
    @IngeBall 4 года назад +2

    Very informative for a electronically challenged person like myself.

    • @D3Sshooter
      @D3Sshooter  4 года назад +1

      Glad you enjoyed it, that makes two off us... `i am by education an electronics design engineer

  • @BleuJurassic
    @BleuJurassic 5 лет назад +4

    was told to use a plastic screw driver to adjust things like this a good video

    • @D3Sshooter
      @D3Sshooter  5 лет назад

      That depends on the potentiometer, if its all metal yes. If it has a plastic cover to turn on metal is good.

  • @fisshayemezgebu8858
    @fisshayemezgebu8858 4 года назад +1

    You-are-a good-teacher!!!!

  • @geofham8332
    @geofham8332 5 лет назад +2

    Hi Steve, great video thanks.

    • @D3Sshooter
      @D3Sshooter  5 лет назад

      Thank you, and my pleasure

  • @ladyshop5203
    @ladyshop5203 5 лет назад +1

    great video Steve Thank`s and big Hi here from Kuwait

  • @minidoido1
    @minidoido1 2 года назад

    Great video.

  • @AliPasha200
    @AliPasha200 4 года назад +1

    Wonderful dear you are a good teacher thanks a lot for sharing such an informating video.

  • @70carlton
    @70carlton 5 лет назад +1

    thanks,...I would have otherwise just asked where the adjustment screw was,....but now I know a lot more,...

  • @yamahattr6006
    @yamahattr6006 4 года назад +2

    Very interesting thanks for the video

  • @Gopherdave1
    @Gopherdave1 5 лет назад +2

    Congratulations on 10k subs.

    • @D3Sshooter
      @D3Sshooter  5 лет назад

      Thank you, but that is all to you and the other subsribers

  • @hisheighnessthesupremebeing
    @hisheighnessthesupremebeing 3 года назад +1

    @13:00 .. The spike is not when the points closes but when they open. When they break the magnetic field from the coil collapses and you get a spark at the secondary side of the ignition coil (hopefully at the spark plug) .. This also results in an inductive kickback

    • @D3Sshooter
      @D3Sshooter  3 года назад

      Indeed

    • @hisheighnessthesupremebeing
      @hisheighnessthesupremebeing 3 года назад

      @@D3Sshooter I know that pointing out a small error like this makes me sounds like a bit of a Jerk.. But when I watch an otherwise very good educational video with a nice explanation of how something work, then small faults like the one above is extra annoying

  • @bencemuller7919
    @bencemuller7919 9 месяцев назад

    Actually your calculations on paper were wrong. If you count 660 rpm, you have a pulse at every 22.7 milliseconds, that's closer to 23 than 22. 4k rpm however should give a pulse at every 3.75 ms. If you solve the 22.7/3.75 equals 6.05, which is multiplied with 660 gives 3995. So your electric adjustment is damn accurate. Now i'm in the same shoes, i have to convert the tacho to v8, you saved me a good amount of money. Thanks! :)

  • @dietmarw
    @dietmarw 5 лет назад +1

    Excellent video. I found it very useful. Have you ever thought of explaining the workings of the old type voltage regulators for alternators that are using relays and possible digital upgrades to get en improved voltage. Mine for example is a bit on the high side (which "cooks" the battery) and instead of trying to bend gaps of relays I'd trust a digital setup more.

    • @D3Sshooter
      @D3Sshooter  5 лет назад

      Yes I did, however I tend to replace the Dynamo's (DC) models out with an Alternator (AC) . As the alternator has the diodes for rectification and stabilization all build in. So no longer a need for the old type dynamo.... Maybe I could a video on it

    • @dietmarw
      @dietmarw 5 лет назад

      @@D3Sshooter In my case I have an alternator that still needs an external voltage regulator. Typically used in japanese cars from 70s to early 80s. They have the diode bridge built in but that's about it. Field windings and neutral point of star winding are fed to outside connectors. I don't want to swap the perfectly working alternator (especially since I even have an identical spare lying around). But regulator upgrade would be something that I would be interested in.

    • @dietmarw
      @dietmarw 5 лет назад

      @D3Sshooter In case it interests you, this is how they are wired up: ibb.co/Yt33MJ6

  • @user-nx7on9sq3w
    @user-nx7on9sq3w Год назад

    Steve your explanation of the working of the RPM meter was very comprehensive just one point in the diagram you have shown the induction coil being in circuit before the breaker point however when you are doing the connection in actual demonstration you are connecting the relay representing the breaker point before the light which represents the induction coil ? will the RPM meter work the same regardless

  • @michelbergh4506
    @michelbergh4506 4 месяца назад

    I enjoyed watching your videos on Smith tachometer wiring and conversion. I have a faulty Jaeger tachometer (signal from negative terminal of ignition coil) and would like to bench test it. You did your work with a fairly fancy signal generator. Would you know of any smaller, cheaper instruments that serve the same purpose? And how could I put my hands on the circuit board diagram of my tach? Thanks much. Kind regards, Michel

  • @motorclockssales5635
    @motorclockssales5635 2 года назад +1

    Hi Great video I'm just missing one piece of information. Can you tell me where i should inject a signal with a function generator on a single transistor model?

    • @D3Sshooter
      @D3Sshooter  2 года назад

      it would be at the same pick point/coil

  • @TheEmbeddedHobbyist
    @TheEmbeddedHobbyist 5 лет назад +1

    Nice video, but looking at the R4 is the adjustable R5 is fixed value of 3K. I've got a misbehaving tacho that over reads. so now I need to know how to remove the glass without making a mess of the bezel

    • @D3Sshooter
      @D3Sshooter  5 лет назад

      Have a look at my part II, its there

  • @motorclocksireland4040
    @motorclocksireland4040 Год назад +1

    Hi, I'm having a nightmare trying to calibrate a single transistor RVI with my function generator. When I inject the pulse it is being dragged high and sending the pointer full scale. I have even purchased the SDG1032X Siglent function generator like yours. Any advice would be greatly appreciated ? I tried to pull the signal to ground but the reading varies according to the resistor I use. Damien

    • @D3Sshooter
      @D3Sshooter  Год назад

      Tell me a bit more how you are using it and possible you have failing components if that does not work

  • @TheJcman72
    @TheJcman72 3 года назад

    I was confused by the tacho diagram, because I thought there was a connection on some overlapping connections where there wasn't (between Q1 and R2 and between R3 and R4). A "go around" connection instead of a straight one, would have made it more readable. That's why I couldn't understand your explanation.
    Thank you for another amazing video.

  • @mzeeraza3516
    @mzeeraza3516 5 лет назад +1

    Awesome 👍🏾

  • @tomvienna1518
    @tomvienna1518 Год назад

    Hi shooter ! First of all thank you for your excellent video !!! I have a Gen 3 RVC Type of a Jaguar V12 which is basically functioning and I calibrated it using an Arduino board to generate the ignition pulses. The meter consumes about 50mA and behaves well when I attach the 3.3V signal between GND and the MIC 2/C input 2 (and even to the blue/white input wire). But the chassis to ground shows a resistance of 96Ohms which makes it non functional when mounted. Where is the connection from the Chassis (and the frame inside the meter) to the signal ground ? I did not yet spot a 100Ohm resistor - is this by design or should I just connect signal ground to the frame ? Best Regards, Tom

  • @geraldbachand9875
    @geraldbachand9875 4 года назад +1

    Very informative video Steve. Thankyou for taking the time. My issue with my Smiths tachometer ( RV1/1240/OO1 converted to neg. ground) is that it reads aprox. twice the actual RPM. Would an opposite wound inductor loop cause this?

    • @D3Sshooter
      @D3Sshooter  4 года назад

      Txs for the comments, No that would not cause it as it is based on pulses. But you might need to adjust the resistor . does it do that all RPM's

    • @geraldbachand9875
      @geraldbachand9875 4 года назад

      @@D3Sshooter Not sure on that. Idle speed seems high (registering about 1200, yet sounds like a proper idle speed), however, on a drive it smoothly increases at all speeds but shows 5800 to 6000 RPM at 50 MPH. At that speed I noticed it would sometimes slowly move slightly higher ( up to 6500 ) even though speed remained the same. I checked my gear ratios and according to those RPM's my speed should be in the maximum range of about 90 MPH. I checked the speedo calibration and it seems quite accurate. If resistor adjustment is recommended could I do this with the tachometer on the bench using a basic 5 amp battery charger? And if so, where would the 2 charger terminals be attached?

  • @ChrisBucknell
    @ChrisBucknell Год назад

    I am just wondering what would be the symptoms of old capacitors. I have a 1972 For Capri Tacho that is not showing any RPM at all. It has power. Would the old capacitors be to blame?

  • @TheEmbeddedHobbyist
    @TheEmbeddedHobbyist 5 лет назад +1

    I was just as thinking that the current pulse has a relationship with the return spring tension on the dial pointer, one pushing the pointer against the other. does the spring lose tension so over time so the tacho starts to over read?

    • @D3Sshooter
      @D3Sshooter  5 лет назад

      Well that is also a factor if the tacho get older and the mechanica parts wear. That is why a calibration is always usefull, trying to calibrate a 4Cyl Tacho for an 8 Cyl is not really the purpose of the calibration potentiometer... but it sure works

  • @macktack2851
    @macktack2851 4 года назад

    just today hauled out a taco identical looking pcb/ component layout but says negative earth will it work with electronic distributer your explanation very good thanks

    • @D3Sshooter
      @D3Sshooter  4 года назад

      Thanks for the comments, as long as you have a coil and you loop de current trough the tacho on a loop it should work. If you have a full electronic ignition, then it will no longer work as you do not have that current loop on the Coil

  • @kevinritter6276
    @kevinritter6276 4 года назад +1

    Thank you very much for taking the time to create such a comprehensive video. A quick question, I have a RVI 1240 smiths gauge out of a 1966 MGB. Is it possible to utilize a pertronics ignition system. It has been suggested that you modify the induction loop to a single pass-through and add resistors to the induction wire. Does this sound plausible?

    • @D3Sshooter
      @D3Sshooter  4 года назад

      Hi Kevin, the principle of he wire loop is to form a coil. The ignition cause a current flow from the battery through the wire loop onto the coil , through coil and out to the contact points each time they close. That causes in essence current pulses in the wire. A classic ignition draws a certain amount of power, much depending on the balast resister and the coil itself. Never the less the current must be sufficient high for the induction pick-up of the Tacho. if that is not high enough then it will not be picked up. For an electronic ignition, that is another story. Here the Ignition solid state hardware needs a DC power supply. So here we cannot use the loop directly. Some electronic systems are coil free, others not and just have electronic braker points. A full electronic ignition will be very difficult ( no coil,no brakers) as there is no such sensing point, unless special provided on the actual hardware of the electronic ignition. A half electronic ignition can work as long as you loop the wire from the ignition output ( the one to the Coil) through your Tacho and then back to the Coil ( positieve side of the coil for negative earth cars). In most cases that will work. Bottom line , its mainly the amount of current that flows through the wire that determines if the tacho can pick it up. a winding less or more might help. I will check that type and come back shortley

    • @D3Sshooter
      @D3Sshooter  4 года назад

      I did check the pertronics ignition system and it seems to be only points. IMO, That will just work and no need to modify anything. You still use the coil and that system is only replacing the points with electronic points. I have something similar in my MGB-GT V8.

    • @kevinritter6276
      @kevinritter6276 4 года назад

      @@D3Sshooter Again, thank you very much for taking the time to provide such a comprehensive response. On a separate note, I also have a Rolls Royce Silver Shadow And have replaced the points with an ignition 123 product which is out of the Netherlands. Basically, it replaces mechanical advance with an electromagnet and obviously provides a more efficient spark. I will send a RUclips video, however, it will not have the production value of the ones you produce.

  • @oxfletch
    @oxfletch 16 дней назад

    Just in case anyone is still reading comments here .... is it normal for the tach not to read anything for about 8s after start (79 MGB 1.8) then be totally fine after ?

  • @r.s.6236
    @r.s.6236 2 года назад

    I replaced my original distributor with the 123ignition. After adjusting my original Smith tacho RVI at 1000 RPM with a strobe the tacho shows higher RPM values against the strobe the higher the engine speed:
    1500 - 1300
    2000 - 1600
    2500 - 1900
    3000 - 2200
    Should the C2 6V/100 be replaced or probably the tacho itsself on the mechanical side.

  • @napoliarmy
    @napoliarmy 2 года назад +1

    Is there a vintage style tacho for a 2 stroke kt100s go kart ? There is no battery on the go kart.

  • @Mr7an
    @Mr7an 3 года назад

    Thanks' for the video, great info! I have a tacho for a diesel (RVP1002/03 D series ford) and need to get my hands of a pulse generator to mount on the back of the pump.
    I'm not sure what to look for as there seems to be some difference between them.
    There are three spade terminals on the back and they are going to the puls generator together with 24v.
    What does the puls generator do, what can i expect for signal, is it some sort of dynamo?
    Thanks
    Christian

    • @D3Sshooter
      @D3Sshooter  3 года назад

      Maybe I can help but would need a bit more info , I assume that you are referring to the pulse generator.. typical that is a loop current connection and a power feed... is you generator a Smiths Pulse Generator TV3203.00A ?

    • @Mr7an
      @Mr7an 3 года назад

      @@D3Sshooter Hello and thanks' for the reply, the thing is, i don't have the pulse generator and don't know what to look for.
      The connections on the back is terminal one "pos" and "Gen Z", number two says "Neg V" number three says"Gen X"
      I have found a pulse generator TV3250/02A but it have only two cables. Thanks' Christian

    • @Mr7an
      @Mr7an 3 года назад

      @@D3Sshooter Sorry for The delay, no i have found a TV3250/02a but not sure IF it Will fit. Its a two cable unit

  • @grayshadowhandpan4277
    @grayshadowhandpan4277 4 года назад

    Hi, Great video! I have an RVI240/OOB positive earth that i got from a friend. He said he didn't know if it works. I swapped the power and ground wires in the back (re soldered to make it negative ground) and wired it in between the coil and the power wire to the coil. Doesn't work. I tried testing the impulse loop, - no resistance, as well as changing the positioning of the wires. How do I test the capaciter or transistor for problems? Would love to hear back. Thanks so much for the video!

    • @D3Sshooter
      @D3Sshooter  4 года назад +1

      The issue is that you cannot just swap the wires, there are transistors and diodes and those need to be replaced or reverted in case of diodes ( zener). Transistors are are either PNP or NPN so depending on the ground use those should be changed. IMO

    • @grayshadowhandpan4277
      @grayshadowhandpan4277 4 года назад

      @@D3Sshooter I cannot swap the wires? This is what I did: ruclips.net/video/ddZ0E2Wd6Ic/видео.html - i swapped the polarity of the ground.

  • @blankschematics3277
    @blankschematics3277 5 лет назад +1

    The tacho jumping about is often a problem on classic cars when updating to electronic ignition, you may need a RVI-RVC conversion board. More info here
    www.mginfo.co.uk/upgrades4mgs/Engines/rev_counter.html#

  • @eketorp
    @eketorp 2 месяца назад

    It’s when points open that spark occurs. Not when they close.

  • @adolphusquetelet
    @adolphusquetelet 3 года назад

    Fantastic video - thanks. A quick question! What is the maximum sweep possible from the tacho if modified? I am trying to find a gauge to modify to create a sweep of about 300 degrees, maybe 330. Obviously 360 degrees not possible, but do you know how far the gauge can be persuaded to sweep if higher voltages applied? Thanks in anticipation....

    • @D3Sshooter
      @D3Sshooter  3 года назад

      Thanks for the comments,Not sure and I would need to test it

  • @233kosta
    @233kosta 5 месяцев назад

    5ms would have given you exactly 3000rpm to adjust to. Mathematically this gives you an ideal ratio as you have an integer for your signal generator *and* an exact line for the hand on the dial to match. Assuming good linearity in the instrument, this should be a good point to calibrate to - it's right in the middle of the indicated rev range, you can check 1500 rpm using 10ms and 6000rpm using 2.5ms (assuming your pulse gen allows it) to verify linearity.
    Then you know it's as exact as it can get 😉

  • @mikedobbels3599
    @mikedobbels3599 2 года назад

    Vree goed uitgelegd.
    Je bent ook in alles beetje thuis

  • @scattkiwiman
    @scattkiwiman 5 лет назад +1

    nice electronics setup. Why not try to build an injection ecu yourself, nice challenge. Works better than carbs :-)

    • @D3Sshooter
      @D3Sshooter  5 лет назад

      hahaha, if I only had the time... Thanks

  • @kevinritter6276
    @kevinritter6276 4 года назад +1

    Is it possible to use a

  • @mikezeestraten7000
    @mikezeestraten7000 4 года назад

    You're joking. You got an electronics lab too. Grounded EDS matting. Hey A mono stable vibrator is just a 555 timer chip and the resistor is external. right?
    Absolutely love the electronic side of automotive eng.

    • @D3Sshooter
      @D3Sshooter  4 года назад

      Thanks for the comments, Yes I am an electronics design engineer from profession and have some old toys still around. yes you can use the 555 for that purpose

  • @m.b.smoshitoa8325
    @m.b.smoshitoa8325 5 лет назад +1

    hello flemish. there are things i dont undestand about you. i see you talking about tachos . but where and how did you get the circuit diagram of it. like also on mf35 you said for inlet valve we use 0.3 mm filler gauge and so so, but where do you get such info. that for this tractor or car the spec for what what is what what. on brixton when you were cheching o2 sensor it had four wires, i was scruitinizing at you and out of the sudden you have already drawn the diagram of those wires. how did you know which wire is which. in fact you did not show us how and where you got that
    m.b.s moshitoa ( s africa)

    • @D3Sshooter
      @D3Sshooter  5 лет назад +1

      Well I am an electronics engineer, and many things are done in simular ways. In addition many diagrams and info can be found all-over the internet/ regards

    • @m.b.smoshitoa8325
      @m.b.smoshitoa8325 5 лет назад

      @@D3Sshooter "I AM AN ELECTRONICS ENGINEER" WONDERFUL, NO WONDER. APPLAUSE TO YOU. I HAVE LONG BEEN WILLING TO KNOW YOUR PROFFESSION.
      AT FIRST I DID NOT EXPECT YOU TO KNOW MATHEMATICS, YEiiiiiiiiii, LATER ON I SAW YOU DOING SOME CALCULATIONS THAT INVOLVES ANGLES AND I WAS SO IMPRESSED. LOL HAHAHA
      I ,MYSELF LIKED ELECTRONICS BUT UNFORTUNATELY I HAD BAD TEACHERS THAT WERE NOT KNOWING IT. INFACT THEY WERE JUST READING FOR US FROM THE BOOK, BUT UNABLE TO EXPLAIN HOW SO. THEY WERE JUST TAKING EVERYTHING AS WRITTEN IN THE BOOK WITH NO EXPLANATION.
      I MYSELF AM ELECTRICAL ARTISAN SO THAT IS WHY ATLEAST I CAN FOLLOW YOU HERE AND THERE ON ELECTRONICS. IN FACT I JUST KNOW THE NAME OF COMPONENTS AND THEIR FUNCTION, BUT DON`T UNDERSTAND THEM WHEN COMBINED TO DO A CERTAIN THING.
      CONGRATULATION. FLEMISH.
      M.B.S MOSHITOA (S AFRICA)

  • @Mercmad
    @Mercmad 5 лет назад +1

    Steve, you going to the Citroen Do? Here's a vid in case you are too busy to go,keep an eye out for a truck like Rusty.
    ruclips.net/video/pzGoKfWWhqE/видео.html