I also ordered the $55 Ultram Tech (from Israel..e-bay) ADF4360-6 based PLL oscillator board. I am going to write my own control that will use a $29 Arduino 2009 board and a 2x16 HD44780 based board with buttons from e-bay (China) rather than running the "5-button" PIC board hack-up the BATC is running. I need to be able to set my own frequencies, so I need source! I have most of the code done already (Arduino is sooo easy..) but I need to figure out some of the settings that the Analog Devices Integer-N PLL / OSC uses.. like "current setting" and "antibacklash". I don't have the Arduino yet.. but I converted some of the Sanguino's that you'll see in earlier posts to actually be Arduino based instead of hacked with WinAVR as I had been using them.
And Yes.. If I do this, it would be a "bang up" poor mans signal generator for 1200-1400 MHz. Code will be open source... Note also that there is a French Ham doing a version and there appears there may also be a board when the BATC CQ-TV 235 comes out in October 2011.. okay.. we are past that.. now.. so "soon."
I ordered $80 of parts from Mouser for the Chip Tantalums (expensive!** only one is really needed for the DSPic33) Bourns Surface mount trimmer pots.. weird SMT 3.3V regulator***, a couple of PICs, and adjustable regulators for the biasing of the IQ circut.. and other bits).. oh and the $27 FTDI module. By **expensive-- I'd eliminate the stinking chip tants-- which I hate-- if the board was re-laid out and replace with common leaded electrolytics.. I'd use standard leaded pots, ***a leaded 3.3v 78L33 type regulator.. those little things would make the board an inch bigger in one dimension but probably cut the parts cost by $15.) I'd also consider the four port FTDI module FT4432 instead of the FT2232 and use one of the extra ports for SPI programming of the Ultram Tech PLL Oscillator and .. maybe an extra RS-232 port with a line driver on the board? Actually, why not put the PLL chip on the board as well and not have to buy the synth from Israel? (No offense here to Ultram Tech.. good service so far)
All parts can be had from Mouser which is the cheapest overall source other than the Analog Devices modulator chip.. the AD8346ARUZ.. that is a Digi-Key or if you must Newark part.
I programmed my own DSPic and saved the BATC pre-programmed one for a second board. I was going to also order another board from the UK and build it up for 70cm. I can't do that. I do NOT believe it is legal to do so in the US. Many including N1ND who is the frequency rules guy at the ARRL disagree with me. I'll briefly mention why I do not think that DVB-S/C/T or even ATSC is legal on the ATV frequencies on 70cm at the end of this post. I might build a second 1255 MHz unit and loan to other local hams so we could do a two-way.. or maybe I'll eventually build up a 33cm unit.
Anyway.. interestingly enough.. the DIP adapter for the PICKit3 I bought to program DIP based PICs wouldn't work the DSPic33... but a breadboard did! If there is interest I'll write up how to make the programming on the breadboard with the PICkit3. Basically hook up the power to the right places and the ICSP lines and power from the PICKit3 and it works! The lesson here: the bread board is the UNIVERSAL dip adapter.. don't waste the money of the ZIF adapter board unless you are programming a lot of parts!
Anyway.. I don't want to ramble to much, so lets cut to the chase. I don't have the Oscillator module yet, so
I fired the unit up with no LO drive and no MMIC pre-driver installed...
It works... At least up to the modulator out from the DSPic33.. Here is a short video of a "government cheese" NTSC SD-box receiving PBS on the Hauppage PVR-150 with WinTV-6 and then streaming it out with the BATC's software to the PIC which at least thinks it's modulating the signal to QPSK (and would if I had a LO and properly adjusted the I/Q offset/drive). So it's really close:
So yeah.. it works like greased snot. It's slick.. and impressive. There are a bag of tricks to make this happen like the MPEG-2 Conexant chip on the PVR-150 configured (in that case, for 3000 MSym/s and 1/2 FEC for 3 MHz wide signal) for a CBR MPEG-2 NTSC D1 video rate of 2222 and MP2 audio rate of 128K which is really quite sufficient for ham use.. actually.. I'd like to experiment with narrower signals!
At 2222/128 the null packets are very small and most times there is negligible PCR lag.. occasionally though the start-up seems to throw off the DSPic33 at this rate and a restart is necessary for a non negative PCR lag. at 2112/128 this seems never to happen but null packets are about 4.5%.. so somewhere in the middle of the two is probably perfect if you want to run 3 MHz wide D1 Video with decent, but not-quite music quality stereo audio! That's at least 1/2 the bandwidth of analog ATV.
<SOAPBOX>
Meaning this should be a shoe-in for the 70cm band! Much better than 2x the quality and 1/2 the bandwidth! Super lets start using it? Not in my opinion. Part 97 defines image on Frequency and/or Phase Modulated signals as designator F2F or G2F only. Commercial definition from researching license grants to commercial parties show that ATSC is 5M38C7W (or in ham speak C7W) and DVB-S as G7W. No exceptions.. I did not find ATSC defined as C2F or DVB-S defined as G2F anywhere! These designators are explicitally defined in Part 97 as "multiplexed data". "7" and "W" are excluded from Image! So even though there is a clause that states that undefined or digital modes that are substantially the same as the analog equivalent in bandwidth for phone and image are legal.. Legally DVB-S/C/T and ATSC isn't IMAGE.. it's DATA. And data is (WRONGLY!) limited in the 1980's rules as 56K baud (symbols per second per carrier) and 100KHz BW .. so even though NTSC video is not legal anymore anywhere else.. ATSC is mandated.. it's illegal in 70cm under current rules but NTSC isn't.
Yeah, would the FCC enforce this or care? Nope. The ARRL doesn't care either apparently. It doesn't change the fact this is what the law says. This is a warning, people. The rest of the world is going digital and as hams we are not. Are rules are a major reason why. They were intentionally set up in the 1980's to make digital modes second class citizens on the ham bands.. or at least new digital modes.
If you disagree with me and run DVB-S/S2 or DVB-C and some have on 70cm... good luck and I wish you well-- I support you.. but I see it as not permissible.. which is really quite unfortunate. It's legal in most other countries that don't have protectionist rules in their regulations.
End of my comments on this... </SOAPBOX>
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