Steven Way back in the bad old days of vacuum tubes and microphonics we found that microphonics arising from audio feedback sometimes could be solved by placing the speaker outside of the main chassis

Hans Right-angle Dupont female connectors are low profile, inexpensive and can be "keyed" to a particular mating plug by blocking one or more of the socket openings. https://www.ebay.com/itm/2-54mm-0-

Al My idea was to determine the tuning range of compressing versus expanding windings. Once known this could predict whether you need to add or remove turns or just adjust turn spacing. Adjustment of

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Might be interesting and informative if some ambitious person would do some tests and make chart or on-line calculator that shows the effect (tuning range) of spreading and compressing turns on a toro

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In absence of a toroid wire length calculator you can simply wind 10 turns around your toroid core, unwind it and measure the length. Then divide this by 10 to determine how much wire per turn. Then m

#20m #toroid

Phil Only Hans could say if there is a software induced delay. It should be possible to measure the delay using an oscilloscope. Arv _-_

#wspr #u3s

In addition to Allison's comments, the filters are designed to work with 50 ohms input impedance and 50 ohms output impedance. If either of those impedances are not 50 ohms the filter cutoff frequency

The left button (S2) completes a series circuit between R44 (3.3K) and R46(10K), with R44 going to +5V and R46 going to ground. If the right button (S3) works properly then R46 is probably not the pro

As mentioned earlier by someone else, compressing or spreading the turns on a toroid core probably does not change the inductance very much (the number of turns remains the same). What it does do is t

If the ATMega328p fuse settings are configured for an internal oscillator instead of for an external crystal that might be causing that no-oscillation indication. _._

Justin N2TOH For small conventions and such, it might work better to have a tiny hand-held HF transceiver. Could be DSB along the lines of a modulated Pixie rig. For near-field communications the ante

#fst3253 #ht #building #vhf #si5351a

Notice that they will not ship to the United States. This is a red-flag that possibly indicates sub-standard components or sub-standard products. _._

https://www.amazon.com/slp/pl259-coax-connectors/h4zgurnh9ocb799

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While unfortunate that he chose to make a very public complaint before contacting the vendor (Hans). This eliminates any chance of Hans fixing the problem without the public attack on him and his prod

Never use your NanoVNA as a dummy load. It is designed to supply its own low-level signal and could be destroyed by relatively high level RF. A suitable dummy load can be built using high power "non-i

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Rahul All is not lost. Your radio is probably repairable. Pursuing that effort will continue to provide education, challenges, and probably frustration. The discussion groups include a large number of

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Rahul Congratulations on your success. Usually it is something simple that takes enormous amounts of time to troubleshoot. Arv _._

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#Measurements using an Arduino ADC Measuring of circuits requires knowledge of what you are measuring, and what you want to see. For HF AC voltages you need either an oscilloscope of a detector type p

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Touching a soldering iron to both sides of each pin might be a good step, but be careful that you do not lift a solder pad. With the CPU and LCD unplugged (and power off) you can use an ohm meter to v

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Rahul Sounds more like a problem with the connections between CPU and LCD (LCD failing to get initialized). Arv _._

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