G8JNJ

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Username: G8JNJ
Joined: December 2016
Visits: 4,291
Last Active: 8:38AM
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Quiet switch mode power supply (SMPS) for KiwiSDR

G8JNJ

October 2024

"And I think the LT1083/1084/1085 stabilizer is a very good and cheap choice."
The 5A linear regulators do produce LF noise.

But adding a big electrolytic across the regulated output helps a lot.

Regards,
Martin
Dozens of CW transmissions?

G8JNJ

October 2024

Most likely during a contest or similar.
When some of the big contests are running, like CQ Worldwide, the amateur bands are usually packed.
Most contests tend to held during the weekend.
This is an
… (more)

Most likely during a contest or similar.
When some of the big contests are running, like CQ Worldwide, the amateur bands are usually packed.
Most contests tend to held during the weekend.
This is an embed external element. It can be deleted using the delete key or the backspace key. To view the full element, press the preview button below.
WA7BNM Contest Calendar: 8-Day Calendar
https://www.contestcalendar.com/weeklycont.php
Follow @wa7bnmcalendar October 9 - 16, 2024October 17 - 24, 2024October 25 - November 1, 2024
Regards,
Martin
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W6LVP Amplified Receive-Only Magnetic Loop Antenna / Where to buy in NZ?

G8JNJ

September 2024

There was an extensive thread regarding the 393WA
https://forum.kiwisdr.com/index.php?p=/discussion/comment/17852#Comment_17852
W6LVP Amplified Receive-Only Magnetic Loop Antenna / Where to buy in NZ?

G8JNJ

September 2024

"I would like to invest in the W6LVP"
Also pretty average IMHO, I'd go for LZ1AQ, used Wellbrook or Cross Country Wireless.
Check out the Loopantennas IO group, ready built PCB's on offer at decent prices.
Regards,
Martin
Antenna Considerations / Do's and Don'ts

G8JNJ

September 2024

When using an MLA-30, I don't think you can have too much gain :-)
Auto waterfall settings can have you chasing your tail. So I tend to set the KiWi waterfall & Spectrum display to manual, zoom… (more)

When using an MLA-30, I don't think you can have too much gain :-)
Auto waterfall settings can have you chasing your tail. So I tend to set the KiWi waterfall & Spectrum display to manual, zoom fully out to see the whole spectrum, then set the maximum waterfall level to -20dB and the minimum to -110dB. This gives a good baseline for comparison with other KiWi's when the same settings are used on them too.
Don't worry about the noise increasing, you should see some, especially in an urban environment.
Just aim for a 6dB increase in the noise floor on the upper HF bands 20-30MHz, when the MLA-30 is powered up.
As I said before, turn the bias tee control to maximum gain, and then just use the amplifier gain control to achieve the best overall performance.
Regards,
Martin
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