Recent posts

#71
Tactical Corner / Re: Sending Encrypted Messages...
Last post by RadioRay - November 26, 2022, 01:58:08 PM
With this entire FASCINATING discussion, there are two , basic,  questions:

"What is your threat model?"
and "
"What information are you transmitting/receiving?". 

If you need to work against a major national power during time of war, it's entirely different from working against your neighborhood kid with a radio scanner. If the information you're passing would fit on a sticky note, a short text encryption method, using paper and pencil is fine.  OTOH, if you're sending 2 megs of battle plans in PowerPoint,also against a nation's security apparatus, that's an entirely different problem.

For the low level survivor coordinating with similar groups, against a nation state enemy with significant electronic warfare capabilities (Ukraine vs Russia), messages need to be short, extremely secure and rarely transmitted. The system keys must be 'incoherent' that is to say random and NOT REPRODUCABLE.  A major killer of intel agent networks in WW II was decrypting back traffic.  If England dropped - Agent A - into France to set-up a resistance organization, safe houses and perons of contact, then he transmitted that all back to England using a MEMORIZED key, WHEN when the Germans eventually capture England's Agent A, they use "practical cryptanalysis" that is; torture the cipher system details and memorized key ouf of Agent A and roll-up the entire network using his testimony and all back traffic (or, as in the Nederlands, they 'play' the network against England for much of the war.).

If YOU being Agent A can recall the system and it's keys to read back traffic, then it's not a one time pad.  If you're using a book, periodical or The Bible for key material, it's not a one time pad. 

So - for a pencil and paper, one time pad it's best used for :
1. Highest security requirement for never being broken.
2. Low volume of traffic, all text.
3. Once the key is destroyed, there is essentially zero opportunity to read actual back traffic.

Remember, if you use a system where you or anyone else can memorize the key, it's not truely a one time pad, for as long as any of you live, and this information will be taken from you by the most extreme means, upon first opportunity of the enemy.

OTOH - I know people so dull, that writing a note in longhand (cursive) might as well be enciphered, because they're functionally illiterate...


73 de RadioRay  ..._ ._

#72
Tactical Corner / Re: Sending Encrypted Messages...
Last post by KE5ES - November 23, 2022, 02:41:22 AM
Five 9 sided dice are a great random 5 number generator for one time pads.  Time consuming but there is a company that produces OTP machines that are stand alone.  https://www.partisanlabs.com/
#73
Batteries & Solar / BMS
Last post by 2M0WHN - November 22, 2022, 10:57:06 AM
Anyone got any idea for a BMS?

Just purchased some 18650's and wondering what type of BMS I would need to use for this project. Hopefully one that can charge from a small solar cell or two that I have laying around so it can be left out to charge or from mains.

Anyone got any links to Aliexpress, UK Ebay or Amazon to get me started prior to soldering.
#74
Antennas / Re: "Sparkplug" antenna
Last post by KE5ES - November 18, 2022, 11:44:14 AM
I was looking for a battery the other day in a backpack and found five antennas I forgot I built.  The sparkplug is nestled in with my Yaesu FT-817nd and works wonderfully.  You just have to cut the wire correctly.
#75
Antennas / Re: "Sparkplug" antenna
Last post by gil - November 16, 2022, 12:36:02 PM
Quote from: KE5ES on November 12, 2022, 07:02:04 PMI got Bulgaria LZ3FA from Texas using the sparkplug antenna and 5 watts.
Excellent! I guess the solar cycle is slowly coming back!

Gil.
#76
Antennas / Re: "Sparkplug" antenna
Last post by KE5ES - November 12, 2022, 07:02:04 PM
I got Bulgaria LZ3FA from Texas using the sparkplug antenna and 5 watts.
#77
Antennas / Re: Do you feel robbed?
Last post by KE5ES - November 12, 2022, 06:27:30 PM
My first dipole got me tons of contacts.  My endfed halfwave is becoming my GoTo antenna.  Yes, Morse Code is far more effective and efficient than voice.  In two weeks I have gotten over 200 contacts on 5 watts with two of them on voice.  The rest are CW.  Some people say "You get what you pay for.". I say use your money wisely.
#78
New To Radio / Re: Yeasu FT 818 ND
Last post by KE5ES - November 12, 2022, 11:00:57 AM
I seem to have bought the last 817 as the 818 was coming out.  It is my go-to radio.  I have talked next door and to Europe with 5 watts. (Morse Code). It has all modes and all bands.  I have a battery cable with attachments for a vehicle cigarette lighter plug, car battery clamps, and connectors for any 12v source I can find.  My all power power pack is a 26,000 ah battery when hooked to the 817 it should run for 20 days or more with accompanying solar panels.  It is worth the wait.  Also, you can listen to AM/FM broadcast stations for local propaganda.  With a small modification you can use it on the CB frequencies if it is legal in your country.
#79
Morse Code / QRP DX
Last post by KE5ES - November 12, 2022, 09:25:23 AM
The last couple of days I have been camping in South Texas.  I am learning Morse Code and have been using it mainly with either my Yaesu FT-817 or the KX3.  With an endfed wire on my DX Commander pole I was talking easily to Hungary and Bulgaria.  My issue is my local EMMCOM wants WINLINK on 80 meters.  It is all well and good but if you are 'deployed' I can't see having the room for an 80 meter antenna.  Any suggestions??  It just amazes me that shack rats expect field rats to use 100 watts on WINLINK on 80 meters.
#80
Tactical Corner / Operation Yarrow
Last post by 2M0WHN - November 03, 2022, 03:21:39 PM
With the UK getting  serious on the idea there may be blackouts over winter here are some recommendations to get through the time the power may be off.


Also the attachment from the UK Government on blackouts and which areas may experience it and what times.