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September 8, 2024. CQ Contest CQ Contest this is XV9_

Holy Smokers it is now full swing back where every weekend is a stupid contest to gum up 20M. Of note yesterday around 7AM local time the Far East was booming through and lighting up my spectrum display on my HL2 SDR. 


One call sign perked up my ears and that was a station looking for contacts from North America and whose call sign began with XV9. In perfect English this DX station was looking for contest contacts. In case you don't know the XV9 was from downtown Ho Chi Minh City (Saigon to us OTs). Wow, 60 years does change things.

There were other Far East DX stations on as well like from Maylasia and Indonesia. One problem here at N6QW -- I had to QRT for my shift at the Board and Care facility, so I reluctantly pulled the Big Switch.

Now something from Lauren Sanchez's boyfriend. It is a 10.7 MHz Crystal Band Pass Filter Why this caught my eye was that I designed a similar circuit for use in my KWM-4 and used it as a roofing filter in one of the conversions. Mine used a +/-3.75kHz filter and with a computer crystal at 10.245 MHz as a 2nd LO, drops you down to 455kHz and on to a mechanical filter. 

You can find 3kHz wide 455kHz filters (KWM-1, and 75A4) and so you could have a full ranged SSB signal. I think this 10.7 MHz filter costs around $26. The KWM-4 1st conversion puts all bands (less 30M) at 10.7 MHz then this filter and the 2nd conversion to 455kHz. 

This also was a part of the solution to the CW problem with the KWM-2. CLK1 on the Si5351 can generate a signal at 455KHz which is keyed in a buffer stage and bypasses the Mechanical Filter.


A Crystal 10.7 MHz Band Pass Filter

It is 4AM and the temperature inside my home was 86F and thus on with the AC so I can write this blog. We have been seeing temperatures well over 105F for the last four days and the kicker is next week we will be lucky to see 75F as a high. There is no climate crisis!

Now to a photo that mates the high temperatures with a solution.  Simply open the doors and stand in front of the shelves to cool down. (Not a really good solution but a solution!)




The bonus is you can snack while you cool down.

TYGNYBNT.

73's
Pete N6QW

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