How about IF tap (10.7MHz) and high speed packet ready (up to say, 76k or faster)?
(Maybe I missed it, but I don't think I saw those 2 features...) 73, Mark N8MH On Mon, Mar 1, 2010 at 1:44 PM, MM <[email protected]> wrote: > My Ideal Competition Grade VHF/UHF Radio Wish list. > > It seems we are long over do for a Competition grade high performance VHF/UHF > transceiver, which can also be used for Satellite operations. There are > several competition grade HF transceivers on the market, however there are no > high end competition grade VHF/UHF/Satellite systems on the marker. > > Most of the rigs I have seen which support VHF/UHF are either HF rigs that > have had VHF/UHF slapped on, or low end VHF/UHF rigs, with HF slapped on. > > If we want the Amateur Radio manufactures to build us a "GREAT" > VHF/UHF/Satellite system, then we need to tell them what we need. > > Here are some suggestions. Constructive comments welcome. > > This radio does not exist. > If the manufactures are interested in providing a new state of the art > VHF/UHF radio to the Amateur Radio community, here is one opinion of what > should be in next Competition Grade VHF/UHF Transceiver and what should not > be in the radio. > > I am going to give this fictional radio a name HR-956-Pro. > > > What do we need: > > • We need a competition grade VHF/UHF transceiver that will support > Terrestrial-DX, Satellite and EME operations (Voice, CW and Digital-JT65). > • The HR-956-Pro, needs to be able to interface with modern computers > (HTML Browser, USB and or CAT-5). > • The HR-956-Pro, needs to able to interface with modern Externally > mounted Pre-amplifier (both power feeds and transmitter sequencing). > • The HR-956-Pro, need to be able to interface with modern Solid State > Amplifiers and Tube based amplifiers. The RF output per band needs to be > standardized with the Amplifier manufactures to prevent transceiver and > amplifier failures due to sequencing problems and RF mismatching. > • TX/RX Sequencer built-in, to control external Preamps, Amplifies and > other accessories (programmable). > > Receiver: > Of course we need a "Great" receiver, not another mediocre receiver. > Each receiver for each band needs to be a "Great" performer. > > No Birdies: > On a HF rig, a few Birdies do not usually cause serious issues, since the HF > users are often listening to signals "Above" the noise floor. On a Satellite > Radio, we are often listening to signals 10-30 dB, "Below" the Noise floor. > Internally generated birdies are a serious problem for weak signal VHF/UHF > operations. > > Filters: > Each mode will need its own selection of DSP filters. The filters would also > affect one of the Line-level outputs to the external PC. There are times > when want to send Filtered or unfiltered audio to your external PC for > Digital signal processing. One of the line-level outputs should be taped > before the HR-956-Pro Filters, the other line-level output should be taped > after the HR-956-Pro filters. The TX and RX filters should be independently > selectable. > The Filters need to be tested to verify they will support Satellite Mode-J > (TX on 2-meters while listening on 435-438) > > Example: > FM-5k, Filters 15k, 10k and 8k filters. > AM Filters 10k, 6k, 3k, etc. > SSB Filters 4.0k, 3.0k, 2.5k, 2.0k, etc. > > Other Modes: > CW, FM-2.5k, Data > > Audio Quality: > Life is too short for QRP or Poor Audio. > It's not the number of contacts that’s important, it’s the quality of the > contact. > On the audio side, the HR-956-Pro needs to be able to support a wider range > of audio through most of the stages. Of course the radio needs to meet FCC > and other requirements, however we can still design the radio to deliver a > wider bandwidth of good sounding audio. > Let's shoot for 100-4000 Hz, on both TX and RX audio circuits. This will > also mean, that a better stock microphone design will be required. > > > VHF / UHF Bands built-in, with competition grade TX/RX: > 6-meters 50-54 > 2-meters 144-148 > 70-cm 420 - 450 > 23-cm 1280 - 1300 > (All frequencies localized for each country) > > Transmitter outputs: > A high power transceiver is less desirable than a low power transceiver. > > Let me explain: > For serious Terrestrial DX and EME you need to run more than 100 watts. A > VHF/UHF transceiver designed for high power ( 100 watt range) transmitting, > would not be compatible with third-party amplifiers or pre-amplifiers. > > Most VHF/UHF amps are designed for 25 or 50 watts maximum input. > > The manufactures of Transceivers and Amplifies need to agree upon a set of > standard power level so the third-party amplifier manufactures can design > properly matched Amplifiers and pre-amplifiers. This will also help reduce > the number of transceiver and amplifier failures caused by mismatched RF > settings. > > Suggested standards for VHF/UHF bases stations: > 6 Meters 50 watts > 2 Meters 25 watts > 70 cm 25 watts > 900 mc 10 watts > 1.2 gig 10 watts > > The duty cycle of the competition grade system, will also need to be greater > than a 70% duty cycle. > A typical EME link running JT65 requires a 50% for 10-30 minutes at a time. > The transistors and cooling system needs to be designed accordingly to meet > the competition grade requirements. > > > HR-956-Pro Must have list: > > Spectrum display screen: > I can't imagine building a new competition grade system without this > feature. > It would be nice to see the band pass, before and after the filter > stages. > > Full computer remote control: > Memory read/Read and save. All memory channels options must be exportable to > a CSV or similar file, including TX and RX frequencies, settings, including > Repeater or split frequency settings. > All protocols must be Public protocols, no propriety software or licenses. > > > Doppler Control (Manual): > > LEO SSB satellites are some of the hardest satellites two work because of the > amount of Doppler frequency change per second. Satellite Mode-B is very hard > (70 cm Uplink and 2-meter Downlink). While you are talking through a SSB > Mod-B satellite, you need to be simultaneously adjusting your transmitter > with every other word, in order to keep your downlink signal centered inside > the transponder. > > The Yasue FT-736R Satellite control knob, seems to work very well with dual > VFO's and provides you the ability to quickly change either TX or RX to > compensate for Doppler (among other features). The Knob style is much easier > to use than "Buttons". I found the Doppler VFO correction on some newer > radios to be very frustrating. > The new HR-956-Pro must have the Yasue FT-736R control Knob and it must be > functional for both VFO's and Memory Channels. > > > DSP Noise tools: > The usual stuff. > > > FM Center Tuning Meter: > Many of the new satellites are LEO's (Low Earth Orbit), and many of these > satellites are running FM-5k. The reason for FM is because the Doppler > causes the 70cm band to drift over 20, kHz during a 10-20 minute pass. The > LEO SSB satellites using Mode J or Mode B are difficult to use because of the > large Doppler change. The FM mode, helps reduce the impact caused by the > higher Doppler. > > The FM Center Tuning Meter feature is a "must have" for a Satellite radio. > When the FM satellite comes in range, just look at the FM meter and tune the > receiver until the needle is centered and you now know the exact downlink for > that Satellite. If the needle is left, turn the RX knob slowly Right, If > the needle is Right, turn the RX knob slowly left, very simple. > The Yaesu FT-736R has a FM Center Tuning Meter and it makes working FM > satellites much easier. The IC-910 has a blinking light to tell you your FM > satellite receiver frequency has drifted. Unfortunately, the blinking light > is useless in telling you if your frequency is high or low. > > > HR-956-Pro, Nice to have list: > > General coverage receiver (50 - 1000 megacycles): > The addition of a general coverage receiver would help with the sales of the > HR-956-Pro. However, it is very important that the general coverage > receiver, NOT degrade the performance of the satellite receivers. We are not > trying to build a super police scanner. One possible suggestion would-be to > make the general coverage receiver a separate circuit board, which would be > connected to a separate antenna port and thus would not degraded from the > performance of the satellite receivers. > > VHF / UHF Optional bands or Transverter: > The Amateur radio community is constantly experimenting with new bands. It > would be nice to have a Transverter module or expansion module for future > bands. In the USA these bands are becoming popular, 220mc, 900 mc, etc > > (All frequencies localized for each country) > > > Size is important: > To hold the hardware, band scope, filters and make the buttons easily > accessible, a box about the size of the IC-756 product seems to be the right > size. > > What should not be in the HR-956-Pro. > > No HF: > No access to frequencies below 50 megacycles. > The addition of HF to a satellite radio would only degrade the performance of > the weak signal satellite receivers. > HF would also add to the cost of the transceiver and reduce its sales > potential. > A competition grade VHF/UHF transceiver has no use for HF. > HF would result in the radio being just another mediocre transceiver. > > No obsolete Serial ports: > No RS-232 or TTL. > These devices are so last century. > > DSTAR: > The DSTAR mode is fun, I use it often and I have even been pushing ARISS to > install it on the International Space Station. As much as I like this mode, > it is not a requirement for a competition grade satellite system. I would > much rather have the money put into making the VHF/UHF receivers the best > possible. > > > How much are we willing to pay for the HR-956-Pro: > > That depends on the performance, suggest price $2000 - $3000 USD > > Closing: > > If anyone knows of such a radio I would be interested to know who makes it. > > > Sincerely > > WF1F Miles > www.marexmg.org > > > > > > > > > _______________________________________________ > Sent via [email protected]. Opinions expressed are those of the author. > Not an AMSAT-NA member? Join now to support the amateur satellite program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > -- Mark L. Hammond [N8MH] _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! 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