Interesting point. Since several years I think that the stronger electromagnetic fileds tha we are exposed to, are frying our brains. There is no other coherent explanation for several human behavior like those truck drivers that uses cells while driving, causing giants catastrophes in our autovias and routes. More than one has got trapped under a bridge because they unknown their height and of the bridge.
The effects of non-ionizing EM radiation on cellular functioning are well known but are kept out of MSM. However there's a plethora of lab experiments and studies. Just 1 fairly recent example:
https://www.sciencedirect.com/science/article/abs/pii/S0093691X06005607I think it needs little imagination on "what else could be influenced?".
https://www.sciencedirect.com/science/article/abs/pii/S0093691X06005607I think it needs little imagination on "what else could be influenced?".
The article posted seems interesring. I'll read it this weekend. Following it I will continue contaminating the ether with my oscillator :-(
Well, there might be some explanation: Driving a truck doesn't require that much of intelligence.
Best regards!
To the people with more experience listening, using or repairing vintage FM or AM/FM sets, tube or sand, this is my question: "to AVC or not to AVC". In my humble opinion it is amost useless except in the case of large sensitivity set near a powerful emiter where saturation or overload of the first stage may be troublesome. I'll learn from your valuable opinion.
Overload at the 1st stage of an FM tuner would impair sensitivity for much more than the IF bandwidth. AGC would do the same but when done properly, without the distortion products. So proper design prevents input overload issues (no AGC). Many tube FM tuners can handle fairly large signals without overload but because IF filtering is distributed (IF stages with IF transformers), the first IF amp could be limiting a few 100 KHz away from the IF center frequency. Not much of an issue because the sidebands of the strong station would cause interference on weak adjacent channels anyway. This is most clear when having built FM receivers where the tuner is followed by for instance, a (no longer obtainable, alas) crystal filter.
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For what it's worth, 21st Century FM receivers normally have AGCs to keep the intermodulation product down to an acceptable level if there happen to be two strong stations at distances delta f and 2 delta f from the desired station. The AGC detector then has to be connected somewhere before the IF filter, as it has to detect strong signals outside the IF channel.
Intetesting points. When young I made a single chip TDA1083 AM radio, a toy only and years ago, the actual AM/FM tuner based on TDA7211 & TDA1220B varicap tuned, but working at eye. Only a VOM I had on those moments. And none of them seems to have AGC/AVC on the FM section. Many thanks for this and future suggestion.
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UPDATE: I had wired the grid circuit of the cascode making the connection of the grid tank to the ECC189. Also I made a crude schematic with voltages but remember that they are completely provisory and may change in the future. Someone asked for the schematic and here it is.
However, it hasn't been tested yet.
My dream is to use SMD components in the RF & FI stages, both capacitors and resistors. I had saved many of them. Below a pic of 1 & 10nF @ 500V.
However, it hasn't been tested yet.
My dream is to use SMD components in the RF & FI stages, both capacitors and resistors. I had saved many of them. Below a pic of 1 & 10nF @ 500V.
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Interesting project, I am working on a clairtone console using ecc85 for the front end and 6BA6 for 2 IF stages. Works well except for limiter function output goes up and down with signal strength.
I don't understand that remark. Ideally the limiter output signal should depend on the phase but not the amplitude of the limiter input signal, shouldn't it?
The limiter needs a minimum of signal to do its job. Perhaps you can improve gain changing old designed 6BA6 by modern 6CB6 as an example, with 1.5 times gm.
Which detector are you using? Ratio detector or phase detector?
Which detector are you using? Ratio detector or phase detector?
I've several EF183's & EF184's but the white painted label is erased. Anyone know anybgood form to distinguish between them? I haven't curve tracer.
Sometimes you can derive it from codes etched into the glass. You could ask it at https://nfor.nl/ That forum is mainly in Dutch, but they don't mind if there is occasionally a thread in English.