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I know, the question seems elementary, but I am having difficulty.? Tony revamped my existing HF for LF and it is working beautifully.? However, right now, if I want to use either one or the other

Been trying out a couple of different preamps lately with the Softrock.? One seems to work fine, steady gain on all bands, but with the other, images are appearing on each side of center.? Why?

Possibly replace the lamp with one that uses an incandescent bulb?

Thanks, Ignacio, not good news for sure.? I was thinking of making and installing an AC line filter in line with the cord since the snap over ferrite wasn't doing anything, but not sure now if it

A problem with these "fluorescent tube" LEDs is that the tube itself acts as an antenna and radiates. Unless the switching power supply is very well made, which is not very common,? its pulses are

Tony's revamping of the HF to LF SDR, and its arrival today, caused me to further track down interference since it was worse on LF.? I've managed to find and eliminate almost all such sources now

Jon https://www.physics.princeton.edu/pulsar/k1jt/wsjtx.html FT8 is amazing. 73 Nick

Thanks for the info, Chuck, but appears to be FT8.? Looks like a relatively new mode which is why I guess not recalling hear it a decade ago.

Olivia possibly. If you do a search, there is a website that will help you ID various modes. Also Ham Radio Deluxe will auto detect most digital modes.

Maybe I never noticed this before, but during my tuning around with the SDR, I notice an apparent communication mode and I'd like to find out what it's called.? I hear it on the lower part of the

3:1 turns ratio; 9:1 impedance ratio; assumes 450 ohm impedance wire to 50 ohm coax.? The original plans called for only four turns around the core, but I found this weak so I used 11 turns. I used a

Jon do you mean a turns ratio of 9:1 or an impedance ratio of 9:1 i.e. a turns ratio of 3:1? 73 Nick

Hi Warren, I can definitely hear and see a difference in SN ratio with and without the unun.? Depending on band, it can vary from 3-6 dB. Can be subtle, but noticeable. I agree about the preamp and

Jon To be honest, I don't see any significant difference between the two plots. Through 30 MHz generally, and certainly below 10 MHz, the absolute strength of the received signal has no importance

I was curious about that too, so did a 30 Mhz spectra comparison, no unun versus unun: https://i.imgur.com/9qRQ4av.jpg I could definitely tell a difference in receive, being stronger with the unun

I guess I do not understand the rationale for a 9:1 unun. The implication is that the random wire has an impedance of 450 ohms. There probably IS a frequency at which the wire has an impedance of 450

The card connected to the Softrock must be stereo. IQ receive output. IQ transmit input. I normally use two stereo cards but it strikes me that a mono card could be used for the mic and speaker

If I remember it correctly, you need 2 audio cards, one for receive and another for transmit. You can use almost anything for transmit, the computer audio card or a USB audio dongle, you don't need

Jon you might find this of interest... https://myantennas.com/wp/ 73 Nick

As you know, made the 9:1 unun yesterday for the random wire and it is performing fabulously well!? Gave the wire new life.? Now the big question is how to weatherproof it as it will be outside all