Herewith is a description of my requirements for an Extreme Rapid Deployment Field Operation.
You will observe that this is highly optimized to perform one type of operation only.
- Rapidly deploy in a park after a short walk during the daytime. Target under 4 minutes deployment time.
- Ultra Ultra simplicity.
- Make at least one QSO within an area the size of South Africa on CW, 7020Khz (in SA) or 7030Khz in the USA during one hour, NVIS operation.
- Utilize a very simple direct conversion receiver with minimum components and moderate sensitivity and selectivity of 1.2Khz or even greater will be acceptable. To be quantified.
- Utilize a very simple CW transmitter coupled to an EFHW coupler and able to transmit 5watts, 500milliwatts or 50milliwatts output power. Measure SWR exceeding 1.5:1.
- Fully understand every voltage, resistor, capacitor, transistor in the circuit and the performance of the EFHW antenna. In other words 100% homebrew.
- Carry 8 separate items in a small backpack.
- A rugged lightweight enclosure consisting of all homebrew circuitry. TX,RX,SWR,ATT,EFHW Coupler, 12V BATT. I don't know the enclosure size yet.
- Handkey (extreme lightweight using a microswitch).
- EFHW 66foot 18awg wire with plug on one end.
- 30 foot slippery cord with fishing weight on one end. Launch 15ft max into a tree.
- Miniature notebook and pen
- Small bottle water
- Obtain a signal report at 5Watts, 500mWatts and 50mWatts
- Give an accurate signal report.
- Do a bit of ragchew
- Confirmation that SWR is less than 1.5:1 using simple LED indicator.
- Battery capacity for one hour operation at 5 watts 25% duty cycle. (this is an interesting part). This is 100mAHr capacity.
The battery size and type needs some experimentation. I have used fancy technology LiPo's in the past. However they are a pain to charge etc and are expensive. So I reckon 9 AAA type batteries would be a good place to start. Will do some research here.
In every case in my experience here in Joburg I have found a tree with easy deployment to 15foot. Then I have found another tree to sit under, about 50feet away with an inverted L type config. The efhw works excellently. I received a 509 report from Pilanesberg over the weekend from a station in Namaqualand Springbok using 2 watts. ZS6JBJ gave me a 559 report from Witbank using 200milliwatts on my K2.
My K2 is a joke for this operation. Talk about overkill!
I now am gathering the parts to build the TX/RX and attenuators. More to follow.