Messages

1

North American Shortwave Pirate / Re: Mix Radio International 6917 was 6880 USB 2302 UTC 15 FEB 2025

« on: February 16, 2025, 0050 UTC »

I moved to 6917.

Thank you for listening to MRI broadcast of Radio 48.

2

North American Shortwave Pirate / Re: Radio 48 via MRI 9755 USB 0134 UTC 06 OCT 2024

« on: October 06, 2024, 0144 UTC »

I was finding a clear frequency out to Europe and Australia.

Thanks for tuning in tonight on the 31 meter broadcast band.

3

North American Shortwave Pirate / Re: Radio 48 on MRI 6870 USB 0008 UTC 28 JUL 2024

« on: July 28, 2024, 1442 UTC »

The added image was not part of MRI’s waterfall. It was from another stations signal running along side.

Thank you for all your posts, email’s, comments, and listening to our station as always. 

4

North American Shortwave Pirate / Re: Radio 48 via MRI 12170 USB was 15170 USB 1928 UTC 25 NOV 2023

« on: November 25, 2023, 1946 UTC »

I moved to 12170. Thanks for tuning in.

5

North American Shortwave Pirate / Re: Mix Radio International 6845<6855<6880 USB 0117 UTC 4 SEP 2023

« on: September 04, 2023, 0323 UTC »

This was a waterfall image test to see the viability of playing music with the bandwidth lowpass filter set and at the same time being able to send images from above the lowpass cutoff frequency.

Thanks for picking them up.

OK. Here's another idea: images on the LSB and simultaneous music on the USB.

If I go that way I would do independent sideband stereo sound with images on both sides.

6

North American Shortwave Pirate / Re: Mix Radio International 6845<6855<6880 USB 0117 UTC 4 SEP 2023

« on: September 04, 2023, 0301 UTC »

This was a waterfall image test to see the viability of playing music with the bandwidth lowpass filter set and at the same time being able to send images from above the lowpass cutoff frequency.

Thanks for picking them up.

7

Equipment / Re: New to me R75

« on: August 11, 2023, 0502 UTC »

I run power SDR interfaced with IF stage and CAT control functions on a modified HF transceiver. I can use the VFO knob to tune with tracking.

I also have the R75 that developed audio distortion. I traced it down in the -5 volt power supply circuit that uses a 555 IC as a DC to DC converter to a bad capacitor causing a low output voltage.

8

SDR - Software Defined Radio / Re: KiwiSDR future/replacement?

« on: July 15, 2023, 0058 UTC »

Nice. I am glad you tried it. I mostly listen to my transmitter in IQ mode. I find it sounds better because in sideband the kiwi has preemphasis. It is not needed on my transmitter since I run preemphasis.

9

SDR - Software Defined Radio / Re: KiwiSDR future/replacement?

« on: July 14, 2023, 2322 UTC »

With my transmitter bandwidth down to 10Hz I can hear a non GPS frequency locked kiwi off by a few hertz when monitoring my station and use headphones that have a very good low end responsive. Even without a wide bandwidth transmitter If you listen in IQ mode you can hear the zero beat drift with stereo headphones if not exactly on frequency.

10

General Radio Discussion / Re: AM STEREO

« on: June 28, 2023, 0557 UTC »

Transmitting in ISB stereo with suppressed carrier is effectively DSB mode. I mostly transmit in sideband anyway. I may get around to working on this at some point.

11

SDR - Software Defined Radio / Re: KiwiSDR future/replacement?

« on: June 19, 2023, 1327 UTC »

I use 1Hz resolution adjustment when the kiwi or receiving station is off frequency. You just enter the 1Hz digit as a user. The digit will not show up in the display but will change.

12

The RF Workbench / Re: Oscilloscope recommendation?

« on: June 18, 2023, 1951 UTC »

I still use HP and Tektronix analog scopes with storage that still are very useful. I also have a Tektronix digital that works in the gigahertz range.

13

General Radio Discussion / Re: AM STEREO

« on: June 17, 2023, 1802 UTC »

Give it a try on shortwave and see how well it works for you. I have been working on a method with two independent sideband channels that would not be subject to propagation fading. The receiving method would be on SDR with standard available modes like dual receiver function.

14

General Radio Discussion / Re: AM STEREO

« on: June 17, 2023, 0452 UTC »

Unfortunately the phase method of C-QUAM that was designed for the the local AM broadcast band can’t keep the stereo and center channel from constantly drifting called platform motion on shortwave. This is because of signal propagation fading causing phase distortion. This makes it just about useless unless you are transmitting closer to the receiving station especially during the day or have no phase fading.

15

General Radio Discussion / Re: AM STEREO

« on: June 15, 2023, 0026 UTC »

I modified a Sony ICF-2010 receiver by bringing out the both left and right channels to line level output from original CQUAM stereo synchronous AM detector IC in the radio. This with the switchable wideband Hi Fi AM filter mod sounds great. One of the best SAM stereo detectors holding lock into the noise without distortion especially on shortwave.