Bitcoin donations to: 1CE9UfWJcHBYkWPns7iqBqZgKhd5xfqEaM thanks!
Buy Bitcoins easily by clicking HERE and get $10 in free bitcoins!

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Topics - swxx

Pages: [1]
Tactical Corner / Nuclear War Survival — How To Survive a Nuclear War
« on: August 29, 2017, 11:18:01 AM »

Nuclear war is much more survivable than you probably realise.
Nuclear war is much more likely than you probably realise.
Nuclear war can escalate much faster than you probably realise.

Tactical Corner / Preparing for an EMP (Electromagnetic Pulse)
« on: August 29, 2017, 11:16:39 AM »
Very comprehensive with lots of information:

Includes How to Protect Against EMP

Tactical Corner / Doomsday Clock: Worse than Cold War Era, now 23:57:30
« on: August 29, 2017, 11:11:24 AM »
Even worse than the cold war:

Bulletin of the Atomic Scientists

Net Activity / Global Radio Relay Network
« on: August 28, 2017, 02:20:38 PM »
If we look at a few logical points: in the event of a Major World Event the break down of communications which have never been so centralised in all history, dependent upon a few important nodes on the internet and satellites, and the fact that these will almost certainly collapse in the event of a major disaster such as a nuclear war, or a major environmental or other catastrophe, then we know that the most likely communications to survive long-term is low-power and predominantly CW communications.

However, with low power and modest antennas (forget 7 element yagis up 30m post TEOTWAWKI) the reality is that even on CW communications will only be reliable, especially for the many coming years of this solar cycle minimum, only for one or two hop E or F layer propagation. Before anyone says ahh but I often work DX using 5W on HF, yes indeed, but not to other QRP and with both sides being QRP also in antenna terms. In this case, during solar minimum, and on frequencies below 10, 12, 15 and 17m (which are not so often open), it is not at all easy and certainly not reliable to have communications beyond a couple of F layer hops or 3,000km or 3,000 miles.

So, let us consider, post TEOTWAWKI, with all broadcast stations on HF either off air or just broadcasting unreliable information or propaganda, how would one get information from OTHER parts of the world, from citizens, using QRP? There are several problems that will make that a very sporadic, difficult and hit and miss affair: days and weeks of endless trying! If you have to listen for 3 weeks to find some news from Australia while you are in Europe, and if you have to transmit for a total of 10 hours to get one single message through to a distant location (calling, calling, repeating, failing, re-arranging etc) then let us calculate: 10 hours of TX at 500mA = 5Ah. 3 weeks of RX at 100mA = at least 33A assuming 16 hours a day desperate listening around. If you had 100W and a 7ele Yagi up 30m, you could likely have done all this with a saving in power! BUT we do NOT have that luxury and we have to prepare accordingly.

For many of us, it is not just important to find out what is happening 10km, 100km, 1000km away, important as that naturally would be, but also, to find out whether there are other parts of the world that are in better shape, loved ones in remote parts of the world may they still be alive (not about getting through to them specifically, that would likely be impossible without normal communications infrastructure working, but just to know whether all of America was wiped off the face of the earth or not, is Australia still an island afloat, is Africa a place to head for from Europe or should it be Scandinavia, etc). So how do we do long distance communications reliably and effectively with QRP power and QRP antennas? VIA RELAYS.

If we have a network of stations running QRP who are one or at most two hops apart, who have pre-arranged schedules, nets, frequencies, and above all procedures and skill in sending, receiving and relaying written messages, then we are able to do this, if we do not, we really are not able to do this.

It is a generally much overlooked reality that on CW "Chinese Whispers" is doomed to failure. Passing a message even with one relay between almost all radio amateurs ends with the message being incomplete or changed. ONLY those who have previous professional experience in formal messaging, and even they are often having no experience of relaying messages, and particularly those radio amateurs who have sufficient experience in "traffic nets" are able to do so. It is very common for "good CW Operators" to think that if SHTF they will be able to relay messages: the reality, proven time and again, is that when they hear <CT> they don't grab a pen and write down, and even if they do, they do not know how to efficiently get fills for missing letters and words, how to check whether the message they have is actually accurate or not, how to avoid confusion in poor Signal-to-Noise Ratio, QSB, QRM, etc. All this is really only learned by on air training in the art.

It would be very good for Radio Preppers to form some new, or join, some existing CW traffic nets, and to start building a relay bridge that can potentially span the globe.

Let us consider some human realities: in a SHTF most of us are not going to be altruistic, willing to use up our batteries passing messages for others! Most if not all of us are going to want INCOMING information, and less willing to give OUTGOING information (which is required for incoming information elsewhere) and almost no one is going to be willing to RELAY information between two OTHER stations. Most will be listening, few willing to send. So HOW do we overcome that? Quite simple! BENEFIT.

If you act as a relay and take part in such a network, you benefit by getting information that you will only get, if you participate and in return, you too are able to send and receive information. By just listening, sure, you will pick some up, but there will be many gaps, incomplete messages, and you won't be entitled to just come on air and ask for this and that repeats and information if you are not yourself an active participant helping the others.

What I'm talking of here though is not an ordinary traffic net, but a relay network. Not everyone is necessarily on the same frequency at the same time. But each sked is to a single hop destination in different directions. A system to route messages is required. A format for the messages to avoid confusion and to ensure reliability. A procedure to ensure accuracy of count, and to find out which word is missing without an entire repeat. I am not going to, here right now, give all that information, you can find it at sites such as Communicators Without Borders and Radio Relay International.

What I am advocating here is that we can start thinking of some training frequencies and skeds to practice and to build up ROUTES along which messages and thus information can be relayed. A difficult task for example: from Europe to Australia. From Australia to South America. Using QRP and simple wire antennas, via relays. Even with 7ele yagi and 1kW, the path from Australia to much of South America is currently very difficult.

So perhaps we can discuss some ideas on how we could practice these things, outside of North America and Australia where such networks exist, what do we do in Europe (so many amateurs but no such traffic nets I believe) and Asia, Africa, Latin America. Among us we may already be enough to stat building such bridges. For long distance reliable single or double hop, we are mainly looking at 40, 30 and 20m. Any ideas on how we can proceed? Are there existing networks we can join, train in and extend? Or do we need new ones that can interface with existing ones?

Technical Corner / Pro and Con of Various QRP Rigs as survival radios
« on: August 25, 2017, 11:23:55 PM »
I'm having a hard time deciding which ways to go between various rigs. Limited finances being a hurdle that prevents me from simply buying them all, let alone one or more. So I'm looking for feedback and hopefully this helps others in the same position of not yet having, or having inadequate, QRP equipment that will be useful at TEOTWAWKI. I have no ability to understand circuits properly nor the likely durability and repair options of the various circuits, so those with good electronics insight please comment on that if you can compare.

PFR-3b: pros: 20/30/40m (fine for tropics, high latitudes may want an 80m set too). Very low power 35mA on RX. 5W (740mA) on TX. Rugged enough. Internal Balanced Line Tuner also for end feds, also coax/unbalanced input. SWR tune. Repairable, many discrete components. Internal keyer. CONS: no wide filter, cannot receive SSB. No general coverage RX. No way to reduce power (I think) from 5W TX. $275 USD.

YouKits EK1C: pros: 20/30/40m (fine for tropics, high latitudes may want an 80m set too). Fairly low RX current 70mA (twice as much as PFR-3b). 5W on TX (900mA). Rugged enough. Internal keyer. Auto scan function. Can turn LCD on/off. Weight 280g. 16 Memories. General coverage RX 5.9-16 MHz. CONS: no built in tuner. No balanced line connector. No SWR indication. Not optimized for 30m. $189 ($239 after adding tuner) USD.

YouKits HB1B: pros: 15/17/20/30/40m (fine for tropics, high latitudes may want an 80m set too). RX current 80-90mA. 4-5W on TX (800mA). IF filter 400Hz-3kHz. General coverage RX 5.9-22 MHz. Forward and reflected power. Built in keyer with auto CQ. Variable filter width can listen SSB and AM. CONS: No balanced line tuner. Ready assembled (could be PRO or CON depending on who you are). $270 ($320 after adding tuner)

LNRprecision MTR3B-5B: pros: 15/17/20/30/40m or 20/30/40  or 80/40/30/20. RX current 20mA, 4W TX (600mA). Very small size could be a pro or a con. Can listen to freq in dark sent as CW, can key in frequency using paddle. CON: no general coverage RX. Non-adjustable narrow filter. Push button tuning, not easy to scan bands. Not more than 12V or damage. $260 ($310 after adding tuner) 3 bands, or $380 for 4 or 5 bands ($430 after adding tuner).

LNRprecision LD-5: pros: 7-22MHz RX AND TX, TX 10.5-15 VDC 3.5-8W (1.5-2A). Voltage on display. Modes: USB, LSB, CW, CW-R, DIGITAL DATA:CAT –USB jack : CW, PSK, RTTY, SSTV. CW offset/tone variable. VOX 0.1-5s. 100 memory storage per band Memorize frequency, mode, VFOs. Built-in speaker 0.2W. 8 Different filters (incl): 4 of 4 for CW/SSB - 1-3 factory presets – No.4 adjustable for CW/50-1000Hz/ and SSB/250-3.6KHz. SWR/PWR. Compressor SSB: 0-20dB. Cons: max 350mA receive (10 times PFR3b, MTR) and 1.5 to 2A typical in transmit. No built-in tuner. 0.54kg. $575.

LNRprecision LD-11: pros: 10.5-15V, 1.8-30MHz+50-54MHz, all bands, all modes incl AM/FM, gen coverage RX (350mA) and TX 5W (11.5V)-8W (14.8V) (1.5-2A), CW offset/tone variable. Effective noise reduction and noise blanker. Sensitivity 0.15uV w/o preamp. 100 memory storage per band Memorize frequency, mode, VFOs. Built-in speaker 8Ohms 0.5W. Vox/bk-in delay 0.1-5s.8 Different filters (incl): 4 of 4 for CW/SSB - 1-3 factory presets – No.4 adjustable for CW/50-1000Hz/ and SSB/250-3.6KHz. SWR/PWR. PAN mode: Easy to Find quiet point +/- 24kHz from main frequencyCons: max 350mA receive, 1.5-2A TX. No built in tuner. 0.54kg. Digital Direct Conversion, SDR type, build-in CPU (SM32a) DSP radio in which RF signals are directly converted to a digital data via differential and balanced A/D converters. This enables direct sampling with extremely low phase and floor noise. $790.

KD1JV Tri-Bander: pros any 3 bands of 80, 60, 40, 30, 20, 17m. TX 5W (600-800mA) at 14V. 2 keyer memories. 600 Hz audio filter. Audio derived AGC. Easy to repair. Built in keyer. Cons: 90mA receive current. No gen coverage TX. No SWR meter, no internal tuner. $225 USD ($275 after adding tuner). Thus don't see advantage over PFR-3B other than if three bands other than 20/30/40 are wanted.

QRPLabs QCX: pros: 17/20/30/40/60/80m (separate units for each band). RX current 150mA. 5W (550mA) on TX at 16V. Double sided through plated silk screen printed PCB. (others above MAY also have this). 200Hz CW filter with no ringing. Keyer, memories and beacon mode. VFO A/B, split. Configurable side tone freq and volume and CW offset. On board micro switch can be used as CW key. Built in sig gen and alignment tools, voltmeter, RF pwr meter, freq counter. Cons: no case included, high current consumption. Single band is not a CON, see below. NO general coverage RX. No wide filter? No balanced line tuner. $150 ($200 after adding tuner) for any three bands (cf to $189/$239 EK1C or $275 PFR3b) or $250 ($300 after adding tuner) for 5 bands (cf to $270/$320 for HB1B).

YouKits TJ5A: pros: 12/15/17/20/30/40/60/80 -- 8 bands. Adjustable power 300mW to 20W. SSB AND CW. Large built-in speaker. 40 memories. Dual VFOs. Low power (10mW) tune up mode. General coverage RX 2-30MHz. LSB/USB/CW/TUNE. Cons: 200mA on RX. Up to 3.5A on TX. Weight 1.5kg. $380

If we factor in that all those above except the PFR3b don't have a BLT Balanced Line Tuner, but we can buy one for $50 or so from or single bands MEF-1 for $15 each then the absence in the other rigs isn't a problem, just an extra cost.

Looking at the above, what would you consider reasons for buying any particular one of the above, instead of discrete QCXs and MEF-1 tuners?

I don't know the cost of a general coverage RX or if available as a kit. But we can assume at very least $50 for such. IN this case if we factor in unit cost(s), tuner ($50), gen coverage RX (assuming $50 minimum) then we arrive at:

PFR-3B $275 (+$50 min): $325 min.
EK-1C $239
HB-1B $320
MTR3 $310 (+$50 min): $360 min.
MTR5 $430 (+$50 min): $480 min
QCX+ $200 (3 bands) (+$50 min): $250 min.
TJ5A (8 bands): $430

The QCX multiple units could be attractive because if one breaks maybe it can be used to repair one of the others. Mutiple bands can be monitored. However, it has very high current drain: 4 times as much as the PFR-3b and double the EK1C.
The PFR-3B looks attractive as an all-in one, but this in itself isn't necessarily an advantage, but its very low current draw is. The LD11 and LD5 are very attractive, but the price may not be easy and current consumption is 350mA RX, 1.5A TX, no way to get it down, cf. to 20-35mA MTR/PFR.

For me it is a hard choice, between pretty much all the above rigs! So it must be a hard choice for most. These radios come close to what is required, but in all cases LACK something. If ONE can fill those gaps, they would capture the market. Prices are ALL fair and proportionate to the rig, except the QCX which gives perhaps the most bang for buck. With increasing features, power consumption becomes an issue. So, the ideal rig:

Ideal rig would be something like the LD-11 with the ability to enter into very low RX current mode (and even lower TX current). Or the PFR-3b with at least 7-22MHz (or alt option 3-17MHz) with general coverage RX *and* TX but with the option to switch various features off to retain the low 35mA RX. Or the QCX with much lower current draw, and selectable wide filter and wider RX/TX coverage. Or the MTR5b with selectable wide filter, ability to get higher power on higher voltage e.g. 8W on 16V, and wider gen-coverage RX/TX 3-15MHz or 7-22MHz. And the ideal rig would be as rugged as possible even if it is a special storage/transport case that is water and shock proof. Ideal peripherals would be matching un/balanced line/end fed tuner, versatile battery holder/adapters, possibly also a power amplifier to 10-20W.

Technical Corner / General Coverage Survival Receiver
« on: August 25, 2017, 09:03:03 AM »
I've been out of the radio scene for 20 or 30 years and I haven't a clue about what radios there are around now, other than the QRP transceivers, which I have researched. So I'm looking for advice here: I have decided the way to go in the absence of a good survival radio, as mentioned in another thread by Gil, that there is not one out there that does ALL the things we would want: 80, 40, 30, 20m at least, on TX, and general coverage at least 5-15 more MHz with wide filter for SSB/AM (even if in SSB). Low current consumption, long life on small batteries, light weight, not too flimsy or prone to breaking.

So I think I need TWO at least: one perhaps the PFR-3b which does 20/30/40m CW and has almost everything I'd need, and a SECOND one for receiving only. Ideally SSB/CW can be as one, no need for AM, so long as the receiver is sufficiently wide. I have NO PROBLEM with a Direct Conversion receiver, in fact, this could be better, as you can hear 3kHz up AND down. I'd want one that does not drift much, is easy for tuning, ie. you don't touch the knob barely and it already shifts 10kc randomly. Low current consumption, light weight, low in price, even a kit that can be built. Not necessarily having digital display, but ideally some way I can return to a frequency.

Any ideas? Do such receivers exist at all, or is everything only amateur radio QRP and QRO transceivers these days?

Morse Code / Q Codes, Z Codes and Battery Life
« on: August 23, 2017, 03:53:41 AM »
.thread went off topic. Cant delete.

Few radio amateurs are good as this, unlike professional service radio operators: formal messages.

What do I mean here by formal message? I refer more to the formal FORMAT of a message.

Radio amateurs are often (but not all, perhaps most are not these days) good at chatting, about WX, ANT etc. all good stuff. Then others are not, they find it hard to exchange anything other than 5NN TU or 73. Same often for professionals who come to amateur radio.

But FORMAL FORMAT MESSAGES (QTC if you like or radio grams) have a very important role for radio preppers. It is all to do with reliability and efficiency of communicating a message and being able to have that message relayed ACCURATELY.

I will give a typical example. IN a net, one station can hear one but not another. So he asks for QSP. He wants to inform the third station that he is going to be unable to make the sked today and will be on tomorrow at 1600Z on 14049kHz. But what actually gets relayed? The station in the middle, listened, did not write down, and then sends the message as follows:

Sorry Bill, John says he could not make the net today but will be on 20 meters at 4pm tomorrow. YET that is completely wrong. So this is why a FORMAL FORMAT is required and a message needs to be WRITTEN (or typed) down. But it has other benefits too:

* Easy to check if something is missing, by counting the words and comparing it to the check number
* Easy to fill in missing letters or blanks by using the "WA", "WB", "AA", "AB", "BN" codes.

For a much detailed explanation of all this, please see -- relating to CW in particular but also applicable to SSB and digital modes:

Of course the benefits are many more: hard copy, filing, third parties, accuracy no matter how many times it is relayed, time and place of origin and clear destination, the importance or urgency of the message.

CW by the way has many benefits over SSB for sending FORMAL FORMAT MESSAGES (QTC or Radiograms). These include as much as 20dB better signal-to-noise ratio thus requiring much less power, e.g. as much as 1W CW to 100W SSB equation. Typically at least 10db but very often more than this. CW can also be copied, by an experienced and trained ear, as much as 12dB or more below noise.

Another advantage is SPEED. Who would have thought Morse Code is faster than voice or digital? Assuming three trained operators: a competent SSB Op, a competent digital OP, a competent CW Op. Digital often needs hand shaking and setting up and a message often has to be typed in and/or printed out before or after the event of sending. But particularly SSB can be very slow and unreliable:

in CW that is sent exactly like that, and if readability is good, requires no repeats.

But SSB will require spelling out:


(because the spaces are important to the word count, remember, any message must be sent or relayed EXACTLY as it was received INCLUDING what may appear to be errors or unimportant things).

The IARU even acknowledges this in the Emergency Telecommunications Guide which is VERY MUCH worth printing out by radio preppers it is up to date, comprehensive and covers a lot of things. This together with any other list of frequencies, codes, things that you cannot access from the Internet or computer so should be prepared in print -- even the message forms/format mentioned above.

Pages: [1]