Part two of a full build of this moderately easy electronic kit, a 5-digit frequency counter and crystal tester. Help support Julian's electronic kit build videos: / julian256
Fascinating series, your explaining things so well, just the right amount of info and it's overall place on the scheme of things. Brilliant work Julian👍
Thanks Dean :) I think the simple kit builds should have all the identification and orientation stuff and soldering tips. The more complex builds probably don't need that stuff.
Ordered. Damn. Should have waited for this video. Now I have to wait for the next video. But also for the packet to arrive. I also ordered some smaller kits you've featured before, looking forward to build and tweak them. Thank you for keeping on posting videos!
I built one of these kits. I vaguely remember running into a few issues that did not thrill me. But the kits certainly are cheap enough, and easy to build.
They're not my improvements, although there may be more that can be done to improve the crystal oscillator. As it stands, it requires modification (the 47pf cap), it's voltage dependent and now I've just discovered it's temperature dependent as well!!! Freezer spray required :/
Julian, Having taught A level electronics to component level in the UK during the 80's and 90's how I would have loved the range of kits available nowadays; this 4pound frequency counter rather than using dodgy calibration scopes with rubbish triggering; 3 pound DVM when all we had were class sets of guess-ometer moving (sometimes) coil meters (dare not let them loose on the AVO) etc. It is a great shame that we are now in a throw away society and just replace the whole board not only because it is more 'time efficient' but also that few people have even the most rudimentary fault finding skills to even diagnose where the problem might be. I enjoy your videos; keep it up. Could you post a link to the designer of the original frequency counter. Regards from sweltering Melbourne. Mike
The variable capacitor is directed to be installed backwards. The correct way is to have the case go to ground so that a screwdriver can be used without bombarding the microcontroller with noise and causing a reboot. I reversed mine, and all is well. The other beneficial mod is to cut the trace between IN and the 102 capacitor, installing a switch. That way, when using the frequency indicator feature you can turn off the Colpitts oscillator which otherwise shunts the signal input.
Hey Jules, enjoy your "banter" and explanations when carrying on with these kits. A couple more you may not be aware of but might want to tackle are: 1) Three Fives Kit (555 timer) and 2) XL741 Discrete Op Amp Kit Both from Evil Mad Scientist. These aren't cheap but would seem to fit in nicely with your electro-educational vblogs. Cheers!
Ok, I forgive you going to bed when it was unfinished. Imagine powering it up and not working last night, it would have been daytime when you got it going then (been there, done that)
By the way, you can actually replace the controller if you somehow damage this one. You can read the content from the controller and store it somewhere, then if the original chip gets damaged you can write the same firmware on it. That's what I did - the controller's firmware is not read-protected, regular hardware for PIC controllers works fine with it.
Hi I have had one on my ' to do ' list for years , its a 7 digit LED one based on the PIC16F84 it includes a 74HC137 and SAB6456 ( 256 divider ) . It has a BF173 on the input and is said to work from 10Hz to 1300Mhz it was designed by Peter Halicky . I found the design on the web years ago but have never got around to building it .
A tip for soldering in sockets (or IC's): first solder the diagonal pins--for ex here--solder pins 9 and 18 (or 1 and10) then while pressing on the socket, or ic, re-wet one of the soldered pins. Very often, you will hear a 'click' as the socket goes absolutely flush with the board--now do the same for the other diagonal pin. You now have the socket perfectly flush on the board and can continue soldering the remaining pins. 'I NEVER solder just down the row'. PS: These are tips I used in many years (decades actually) of soldering and designing circuits and then laying out and assembling my designs. So if anybody see's a bad idea, please say so. --daLE
The trimmer cap is to calibrate your oscillator. Otherwise you are only checking if the crystal under test oscillates and not how accurate it is to its design frequency but with only a 5 digit display its really only a rough guide to its frequency anyway. Trimmer caps have always been used to adjust crystal oscillators but it will depend on the accuracy of the required clock out. Today's oscillator modules are typically more accurate and do not require adjusting but are sometimes temperature controlled for stability.
Sent for kit so interested to see part three! Banggood do a similar one but don't think it has the variable cap and has a different component layout. Makes you wonder about the amount of product testing that takes place, if any, before going on sale!
Damn you Julian!! My eBay bill has gone through the roof since I started following your channel. And even my wife and daughter want to learn to solder - what the hell is that about, that's just weird :) Love listening to you. "I prefer "puff" (PF)" Lol!
I had to see part two after watching part 3. I had to see you suffer. But anyway good work, sometimes electronic challanges takes guts. I was eyeballing how to reprogram it for anything but its assinged task. Also, not soldering the pwr jack that fits nothing, causes some pwr issues. The show is great!
Nice job. TheHWCave has a mod to change the xtal osc into a pre amp..a substantial improvement in sensitivity (rather than the TTL input levels needed), and offers some protection for the PIC from direct exposure/damage from the input signal. However, the EZM Electronics Studio version, with the preamp it has, far exceeds it in sensitivity.
Thank you for this video series about the frequency counter kit. I need a cheap way to measure oscillation frequency for my low power chinese induction heater experiments, in the 20Khz to 120Khz range, so this one should be just fine. I found it for sale for USD$3.98.
When I soldered in the digits (on this very product), I felt a little OCD and I needed them to be straight so I put them in my vise. It worked pretty well. Julian, will you put this with a series of shift registers to make a super-simple, LED-based logic analyzer?
Hi there! If you intend to only power this off a 5v supply, such as USB, would it be possible/advisable to bypass the power regulator, so you don't have to worry about voltage drops?
Julian, is that component tester, which you used to measure resistor values, capable to measure crystals frequency? if it can, how's it doing compared to this one?
Hi Julian, i have been wondering for a while, whats that blue rubber elastic sticky stuff (blue tec?) you are using. And where to get this? Seems very handy. Regards, Fred.
Blue-tac is on the way to becoming a genericized trademark in the UK. The more general terms museum putty, mounting putty, and earthquake putty will probably suffice for getting what you want in a craft store wherever you live. I have some in the drawer made by Loctite called Fun-tak.
Julian, I've same Kit and also a Kit with yellow PCB. The programed controllers of both are the same. The kit like yours I got to run after 10 Minutes. The kit with yellow PCB doesn't work right now, I need more time to get it work. Well, just to measure a crystal, the kit is very good. But I made experience with hold the botton about 7 seconds and I got absolutely no manual what does the chip do in this situation. May be you get more information about this and maybe you can report about this in the next video ....
Can you sir show me the tutorial for the test display that you using for testing resistors etc . I realy want to build one ^.^ And ofc thank you for the many educational vids . i realy learn allot from you Can't stop watching all these fun micro components stuff
I did one a year ago, same as yours. Was missing the 9018 from the kit, and only had one set of pins for the crystal readings, didn't have one for the frequency counter (also missing ground). I added another 9018 and at 5V off USB it just reads to 30000 all the time. So I added the extra 22uf cap and no difference. I think the variable capacitor has to do with the driving of the display? If you mess with it the refresh rate changes on mine. But I gave up, maybe I should go back and trouble shoot it to see why this cheap kit didn't work. I think I was tired of cheap kits missing parts and waiting 6 weeks for it and gave up on kits all together and started pref boarding schematics instead with parts I knew worked.
Now that I'm at the end of your video I agree, their are multiple issues with it. My micro controller works since I can access the offset and zero menus. I think it's all about the voltage and oscillator part that is a bad design.
It was an additional 22p, I typed the wrong one. It's in the instructions I found on the second page of the PDF. Basically adding to the one capacitor. Or I could have changed it to a bigger capacitor as Julian mentioned he did. goo.gl/00Nc8g
I got my answer: they are multiplexed. Couldn't be different as of only ~8 resistors :) I have used multiplexing in a LED-matrix but not on LED segments but thats ofcourse works the same *hit myself on the head*
I think a big issue may be that the transistor oscillator circuit does not give you nice clean square waves, unlike a typical Pierce oscillator using CMOS gates. Also single transistor crystal oscillators can be very fussy about the exact components chosen.
Hi, thanks for your videos. I write for help. A few days ago my frequency counter arrived but it does not work, I insert the glass but there is no reading and sometimes strange numbers are seen. Compare this kit with that of another seller and noted that the only difference is the type of LED. The one that does not work has common anode LEDs and the other is a common cathode, I read on the creator's page that sometimes the copies come with the wrong LED type. Is it possible that by having the wrong type of LED your can see the letters of the menu but when the measurements are done they are not displayed properly? I exchanged the PIC with another kit and I still have the same problem, will the transistors be? I hope someone can help me because I am not an expert. regards
Isn't the variable capacitor so that you can calibrate the capacitor pairs to be as close as possible, to cancel out any tolerance errors in manufacture. EDIT: got to the end of the vid, and you mentioned that, guess you just need a known good source for you to calibrate off of.
I don't even think capture compare would have worked the timer would still only run at 20MHz (or is it even just 5MHz because it's a PIC an uses the system clock? Don't remember). So you can't capture something that's faster then that. Here you just let that external clock make the counter tick and see (with the system clock) how long it takes for the timer to overflow.
I have the same unit and another different unit with the yellow button. Both units will NOT read above 20 MHz properly. example, 37.600 MHz displays 15.53xx. Other 37, 38 45 MHz crystals show similar results. They 'divide' by 3-ish and that's what they display. Anyone know the fix?
Know what you mean wasting time adjusting the cap, esp with a metal driver. Influence of the screwdriver just touching it seems to add about 10pF capacitance on top of the actual value. You might get it precise but it's pointless unless it's a frequency standard or precision oscillator.
There appears to be two similar offerings of this type of device on e-bay. Perhaps this other one is better : ?? www.ebay.com/itm/DIY-Kits-1Hz-50MHz-Crystal-Oscillator-Tester-Frequency-Counter-Meter-Case-New-/252544299630?hash=item3accd0326e:g:ZWkAAOSwPCVX3WgT
Ispike73 , I've just ordered one of these. It's pissing me off that the default, nothing-connected *zero* it displays is not on the centre 7seg. I'm gonna have to reprogram that PIC...
Julian why don't you use a fume extractor? 2) build a fm transmitter kit also 3) build a power amplifier kit too. I don't remember the kit number but it was tda something something it could power up 2*15W speaker for just a dollar delivered
A single transistor oscillator will never properly work for a large frequency range its just a inherent property of how a crystal oscillator works. A single transistor oscillator will always be capacitor and voltage dependent. Even worse the actual frequency of the device under test or crystal in this case can drastically change under improper driving conditions. See en.wikipedia.org/wiki/Crystal_oscillator#Spurious_frequencies for more details on these none desired properties of crystals
I recently bought one of these kits with the intention of using it as a frequency counter. It's turned out to be useless because it switches itself off if the frequency does not change after a few seconds. According to the description, this power save option is supposed to be user configurable. I believe the way it is suposed to work is that if you hold the push button down for a few seconds, the firmware should enter 'program mode'. This should provide a menu of configuration options, one of which is 'power save'. See www.qsl.net/dl4yhf/freq_counter/freq_counter.html#how_it_works The firmware in the kit I bought does not appear to have a 'program mode'. Another problem is that the least significant 5th digit is considerably brighter than the other 4 digits. I think this is because there was no free output pin available on the PIC to drive a fifth digit so a logic combination from the first four digit multiplexer outputs was used. This results in a higher current for the fifth digit.
Kyôdai Ken because needle sharp pencil points tear paper and are more prone to breaking. .5mm pencil leads have a long history of this and why .7mm pencil leads exist.
Is the designer one Wolfgang "Wolf" Büscher? I hesitate to post the link to his design only because (a) it might be the wrong chap and (b) he's specifically asked not to be asked for help with these kits as he doesn't manufacture them!
Julian Ilett Yeah I see that everyone hates it. Thanks I'm new into this stuff so I want to know what Im doing and your videos tells alot how to do it and how easy it is to do thanks
yeah i hate it my self, damn stuff takes to damn long to flow and then it needs a lot of power and heat to get there and it still flows like molasses with outside temps.
@12:56 you mentioned to drive 40 LEDs you need 12 pins. This is not true. To drive each segments of a display you need 8 pins and for 5 nos display you need 5 pins. SO TOTAL 13 PINS NEEDED. Multiplexing is not at all any complex mechanism. You just need to drive one display at a time. Allocate 5 characters buffer and drive out each value to each displays along with its CC pin. If you do it very fast then our eyes will not see the flickering. Sometimes when you drive it very very fast then you may need one or two blanking cycles to add in the algorithm. This is because the internal switching transistor doesn't come out from saturation level immediately hence a very faint glowing could be seen on segments that are OFF for that digit. This blanking helps the process to stop current flowing through it. In fact its very easy to multiplex displays when a microcontroller is being used. Would request you to watch your video at least once before uploading to see what mistake is there and you can then annotate it on youtube. This way beginners will not get puzzled with it.
Yes, you need one pin for each segment, but since only one digit is driven at a time, you can encode it (in binary) and decode externally (with diodes for simplicity). So 8+3 pins for eight 7-segment displays.
There is a common pin for each digit. So you are bound to drive each digit at a time and there are 8 resistors for that. All the 8 LEDs of each segments are driven at once. Can you imagine how complex this board would be if you need to decode binary decoding with diodes ? you cant do it using diodes alone. Instead if there is shortage of pins, then one can drive the multiplexed digits using shift registers like 74HC(T)595 kind of ICs which are readily available and cheap as well.
+Satyajit Roy I stocked these BCD chips CD4511, they need 3 input resistors on the BCD lines and 8 for each LED of the segment, but I think multiplexing is better (less resistors)
Yes this CD4511 was one of the component used to multiplex 7 segment displays in old days. BCD stands for Binary Coded Decimal which means the the digital lines carrying binary information will go up to 10th value (0 is one of them). For example if you have 8 lines to carry two signals for two numerical digits. then in theory you can have 7 lines more than adequate. because the 7 lines means it can show max value up to 127 (2^7-1). In some circumstances, these 7 lines is problematic to decode into two digits. Because you need to decode the 7 lines in one chip. But if binary code the decimal value then via 8 lines you can distribute the information for individual digits. This way you can easily use 4511 like ICs to show the numerical value. In todays world this BCD format is useful sometimes. The Real Time Clock chip like DS1307 still uses this BCD encoding to keep the timing information. The same technique is being used in many moder micro controllers such as ARM processors to keep the timing information internally. When I was little kid (around 30 years ago) I used this CD4511 for one of my design. Yes literally was one of my design at that very young age.
do you know a good place to buy bulk assorted ceramic capacitors and 1/4 w resistors? I'm trying to get a good number of them and just never have to buy any in the future. are eBay resistors and capacitors of good quality? www.ebay.ca/itm/182390406063 www.ebay.ca/itm/151128848522 which component tester are you using?
The resistor kit looks pretty good - a good spread of values. Sometimes these kits have lots of low ohm values and high megohm values with not much in the middle.
ClassicPork You are absolutely secured by AliExpress. You are protected like with PayPal. İf the order do not come within 60 days or is faulty/damaged, AliExpress pay you back and get themself the money from the seller. After finding AliExpress for me eBay is finished.
I bought one of the kits, and perhaps I should have found the item at one of my favourite and trusted vendors (like alice...). Then I would probably not be looking around for spares to make up those missing in this basic and simple B.O.M. :P
Please don't do anymore screen captures with voice, as it's really shit, get a new computer, Linux if possible, windows if needed. just get yourself a faster computer
