The FLEX-6700R™ Signature Series receiver is based on a new
hardware architecture and SmartSDR™ software platform. This hardware
uses Digital Down Conversion (DDC) to convert from RF to digital. The
FLEX-6700R uses two Spectral Capture Units™ (SCU) for the RF to digital
conversion and an ultra high performance on-board signal processing and
control system to perform demodulation, filtering, and audio stream
management. The result is incredible receiver dynamic range and
received signal clarity.
The FLEX-6700R model
receiver utilizes two SCUs for reception from 0.33 to 77 MHz plus 135 to
165 MHz and the ability to create up to 8 full featured independent
SLICE RECEIVERS. Optimized preselector filters can be selected for the
ham bands for greater out of band rejection.
SmartSDR
is the “ecosystem” of the radio platform. It organizes all the signal
processing power in the radios into an advanced radio fabric. SmartSDR
understands the capabilities of each SCU and how to harness its power.
It also comprises of the “presentation layer” or GUI client that the
user interacts with. The FLEX-6700 utilizes an Ethernet connection for
high-speed “driverless” access to the graphical user interface (GUI).
Now I know there are people around with too much money and there are some applications when a very good receiver may be of benefit, but would YOU spend £4799.94 on one? This is just the receiver remember! No thanks. I'll continue to build simple rigs for a few pounds and accept their limitations.
Despite promising to finish off the 472kHz transverter properly first, I decided to have a go at the TX side of the 10m DSB WSPR and PSK transceiver (WISPY). Starting with the PA and working back to the drivers I breadboarded a simple linear amp based on a couple of 2N3904s and a 2N3866. Power out is around 1.2W pep. I also added the osc/doubler and single balanced mixer later but have not optimised the overall strip. This phone image shows the breadboard I was working on - not a pretty sight. If time allows tomorrow I'll continue this and maybe get to hook it up to an antenna and a PC on TX.
At a recent EME conference in Cambridge John Regnault, G4SWX demonstrated EME using WSJT by remotely operating his 1kW EME station (using the call GB2EME) located on the east coast of the UK. They worked well over 100 DX stations off the moon during the conference (which I did not attend). Joe Taylor W1JT who invented WSJT and MAP65 (and WSPR!) was there.
Although I'm an engineer who enjoys doing "a lot with a little", one has to be impressed by the dedication and sheer hard work some amateurs put into the hobby. Recently G4BAO demonstrated to me his 10/24GHz station which has software controlled rotators, mast top RF sections and GPS locked SDR receivers. He was able to make state of the art 10/24GHz narrow-band operation look easy, when in reality it was the culmination of a lot of very hard work over very many years. Of course, the effort goes on and on.
The latest edition of Land Mobile Magazine (a magazine for professionals in the mobile radio business) has an interesting column showing how London Eco-Routemaster buses are being fitted with a novel sort of bell push (the kind you push to ask the bus driver to stop) which harvests energy from the action of pushing the bell to send a wireless signal through the bus to the driver. The bell push uses an energy harvesting chip from EnOcean a company that specialises in such devices.
The EnOcean evaluation kit (for professional developers) as shown on their website
This is the first time that I've seen a very practical use for energy harvesting. I assume that the device "harvests" kinetic energy (from the pushing action) and thermal energy (from the finger tips) but it must generate a few uWatts for this to work. So, no batteries, no wires, wireless comms and good for 300k presses. There has to be a QRP application!
Back home now, so it is on with the autumn projects list.
Several people have been contacting me about the latest 472/500kHz 10W transverter. Someone in OK-land is designing a PCB and I hear a "dead bug" version has been successfully built in the USA - not sure whether an exact copy or "based on" - but it has already been used on MF WSPR with a report from over 2000km up the USA east coast. So, I will continue with refining this design first and then get on with the "WIPSY" 28MHz simple WSPR transceiver next.
The non line-of-sight optical beaconing tests will resume a little later when the evenings start to draw in. I want to set up a more powerful, semi-fixed 481THz optical beacon so that I can do a series of DX tests under various degrees of cloud cover. Tests last winter suggest much further will be possible than the 9km NLOS ranges achieved with clear air scatter when signals were audible by ear. By using much lower sub-carrier frequencies the optical detector sensitivity will be very much greater allowing even weaker signals to be detected on QRSS3 and QRSS30.
Sorry for the absence of postings last week but we've been on holiday. No ham gear with me, but I did spot several nice HF and VHF yagis on my travels.
Several of my blog readers were DXTV enthusiasts (like me a long time ago), so I wonder who will be the first to identify where we were on holiday by this testcard copied at 4am this morning on the hotel TV? No prizes for giving me the country, but interested to know how many out there know the answer and whether or not this card has ever been copied in the UK on Band 1 TV. This was on 625 line UHF.
My son Tim Lapthorn, who is a professional jazz pianist, is holding a concert in Oxford on Sunday Oct 7th to promote his new album. All proceeds will be donated to the MS Society. You are most welcome to attend and enjoy.
"Benefit concert for Multiple Sclerosis Society. Tim Lapthorn and his
trio will play material from the forthcoming album, Transport (Pathway
Records) which includes brand new original material. The group will also
play reworkings of jazz/folk standards. Please come along to this very
special event to help support a great cause!"
This afternoon I managed to do a little more work on the WSPR transceiver for 10m, building the oscillator/x2 multiplier stage and the balanced mixer for the TX part using a couple of 1N4148 diodes and a T50-6 tuned circuit. Carrier suppression is around 30dB without much effort. Next stages will be to add a linear amplifier to bring the DSB output to around 1W (500mW pep SSB carrier). Although I could combine the same mixer on RX and TX, I may stick with the Polyakov RX mixer as this is working so well.
I should have added that with a linear PA, the WISPY transceiver should also be perfect for PSK31 as the 14.060MHz crystal (when doubled) will certainly pull to the PSK31 10m sub-band.
Icom have announced that they will be introducing a new multi-mode, multi-band radio called the IC7100 which includes 70MHz at 50W on some versions. This is, to my knowledge, the first time one of the big manufacturers has properly included 4m in the design. I know at least one Yaesu rig was capable of working on the band, albeit with some compromises. The new Icom rig has a separated control head with a sloping front, which is ideal for desktop operation and mobile. It will be interesting to see the price and when it is likely to be launched. Also, whether or not they intend to do a 10W version (like the IC703) which was very popular with QRP enthusiasts.
Although not in the best of shape today, I spotted CX1BP (11131km) and EA8FF on 10m WSPR today. Not bad for a handful of cheap parts.
I had a bit of trouble today with the SE602 I was using for the TX part of WISPY (it may have been faulty but I was unable to get a clean DSB signal out of mine), so when I get back on the project after a week of interruptions coming up I'm going to go for the simple 2 diode single balanced mixer instead on TX. I know this works well and is less expensive. The TX part can be simpler than the RX I believe.
