I must say that i am glad that someone else than me found this interesting circuit originaly made in Japan by unknown guy. Ok forst time i build it i use similar coil like you 8mm plastic body from old AM radio winding this 6x1 x 2 windings ..then i found small toroid from old florescent lamp 15W and wind ..this time bi-filar so ..6x2 turns and i get better results . In fact work really well.For diodes i think that author says silicon..so i have 1SS93 and use it also work well. I use this ratio detector for my ONE TRANSISTOR FM superhet radio.
@hotshotmarketing4893
3 жыл бұрын
I have not done a lot of testing with different types of diodes but did order some germanium ones from ebay that I am waiting for. Once I get them I would like to see what happens to the sensitivity. Also I should point out that there a lot of fake ones on ebay and found a web site that said most of the small style germanium diodes did not work nearly as well as the older style large glass body ones. So even though I thought I had some germanium diodes, I may really have had fakes so will do some more testing on this.
@astongoldsmith2396
3 жыл бұрын
@@hotshotmarketing4893 do you tested circuit on 10,7mhz
@hotshotmarketing4893
3 жыл бұрын
@@astongoldsmith2396 Yes, I only tested it on 10.7Mhz. I made a front end with NE602 mixer to mix down the carrier to 10.7 MHz. I then fed the 10.7MHz to a 10.7 MHz ceramic filter and 3 stage tuned amp and finally to the ratio detector. The audio sounded very good but over time the mixer oscillator drifted so I still want to add automatic frequency control feedback to keep it tracking the carrier frequency. Hopefully I will have a chance to do this soon and will then add it to my channel and add a link from this video to the completed fm radio.
@astongoldsmith2396
3 жыл бұрын
Yes i also would like to see how demodulate 10.7mhz
@ankurpaul1
3 жыл бұрын
Great Video. Can you show its working with 10.7 mhz IF signal from a radio.
@hotshotmarketing4893
3 жыл бұрын
Hi Ankur, I did build a receiver for this but still want to add an automatic frequency control for it since even though it does sound good, the Local Oscillator on my receiver drifts over time. Once I finish it I will add it to my channel.
@metatechnologist
2 ай бұрын
I mean we all know that the ratio FM demodulator was invented decades ago by RCA, right??
@deuce-way1440
2 жыл бұрын
Hello, what gauge wire did you use on your torroid ?
@hotshotmarketing4893
2 жыл бұрын
I did not test the toroid version since the toroid's I have are not the same type but did order the correct toroid's today so when I get them I can do a test to see if they make any difference. The wire gauge I used on the coil form is 32 AWG and not 26 as mentioned incorrectly in the video. There is nothing too magical about the wire gauge but you will need to use enameled wire. You may be able to fit on a thicker gauge as long as it fits on the form but I would recommend staying close to 32 gauge since you could have other issues if you deviate too far away. I would not recommend to go thinner since you would have lower Q which could also change results. They only way to know would be to experiment.
@astongoldsmith2396
3 жыл бұрын
what is a diameter of your coil i have 6 mm plastic body with 4mm ferite core for tuning
@hotshotmarketing4893
3 жыл бұрын
The ones i have are 5mm and can be purchased on Aliexpress from: www.aliexpress.com/item/32983728237.html?spm=a2g0o.productlist.0.0.1e002ea0ngUeKP&algo_pvid=3f1373f0-bf6f-4e7b-9439-c456f4768322&algo_exp_id=3f1373f0-bf6f-4e7b-9439-c456f4768322-9&pdp_ext_f=%7B%22sku_id%22%3A%2266773799784%22%7D If the link does not work just type in variable inductor and you should see it. I bought the forms and wound the coil using number 26 enamel wire. Your cores could work also but you may have to measure the inductance. I would recommend to order the same cores since they are very low cost. Also I can't remember which meter and test frequency I used to measure my inductor so if you use a different meter that uses a test frequency it quite different you will get a different reading. I hope this info is helpful. I did make a working receiver using this detector. It does sound good but I still want to finish adding an Automatic Frequency Control circuit to the receiver since it will drift over time. I also would like test a phase lock loop audio detector circuit to see how that works.
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