[Flexradio] Preamp question
Should the preamp be affecting transmit? I set up my tx filter from 200-1200 for psk and using the VAC. With preamp on low the display shows a pretty wide base of the signal. On Med it's a bit narrower and with about a 10db spur on the low side. With the pramp on high I get a very narrowly defined tx signal. Is the signal actually not changing but just the way the display is representing it? Even if so, this seems like the preamp is somehow effecting the tx chain. Still getting some popping on the VAC, but only occaisionally. I tried changing the VAC settings to various values between 30 and 60 and all seem to generate more popping than the 20 settingmaybe going in the wrong direction? Tnx Greg AB7R
Re: [Flexradio] RFC - Poor Man's Universal Controller Board
Larry Thanks, I have never had and amp so really don't know the keying schemes. I would imagine that most are quite benign, however, a little relay in x2-7 would put an end to the question of spikes, voltage and current. Also 5V at 50 mils is available for the relay. Most feet switches or hand switches have all be 1/4 inch phone jacks, and although everyone hates the 1/8 inch jacks, the 1/4 is a little large to put on a self supporting mini circuit board. If a little board is proposed, it does make sense to make the other pins available on a header. Lemme know what you think. I think we can design the board ourselves, however Tony said he could whip it out. I surely would be less expensive then ruining the chip in the raid, and rival what users can do by jury rigging a 15 pin connector as I did for the foot switch. Eric -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Saturday, November 19, 2005 11:45 PM To: ecellison; FlexRadio@flex-radio.biz Subject: Re: [Flexradio] RFC - Poor Man's Universal Controller Board E^2, I'll give it a runthrough and see what should be on a little board to isolate the big bad world from the delicate innards of the ULN 2003. What I did for X2-7 was put a diode cross the relay coil in my Drake L-4 amp as that coil puts out over 400 V on the back voltage. The coil is driven by a 30 VDC supply and draws 50 MA when the transmit line is grounded. What else do people have in amps? Control line specs? I know there are already several widgit boxes on the market for the amp control interface. We need to have the rest of the input/outputs protected and incorporate the amp control in one plugin. 73, Larry K2LT drakerepair.com 800-687-9161 From: ecellison [EMAIL PROTECTED] Date: 2005/11/20 Sun AM 01:59:34 WET To: FlexRadio@flex-radio.biz Subject: [Flexradio] RFC - Poor Man's Universal Controller Board Folks I think I blew the ULN 2003 open collector chip out of my radio during the Belize DXpedition by trying to connect a relay in an amplifier directly into the radio on x2-7 without any buffering. Perhaps a spike or surge. Dunno. But it brings back to mind a project I suggested to Tony - KB9YIG who has done a fantastic job designing and refining kits for the SDR-1000 and is currently totally immersed in the SoftRock40 SDR. At one time I had suggested a Poor Man's UCB to connect dedicated and open pins to the X2 15 pin connector. It was shelved and deemed not necessary since users can plug just about anything into the X2 connector and experiment. As a result of my experience, I'd like to 'throw' out an idea to create an inexpensive PC Board to protect the X2-7 output to control Amps etc, with a 5 v relay and provide jack for a cold switch to ground for X2-10 PTT input. X2- pins 1 thru 6 could be brought out on a 6 or 10 pin Berg connector for readily available ribbon cables to interface the control lines to some external device, like a universal controller board or for experimentation by users in a breadboard. Having a little external board connected to the X2 connector perhaps with opto isolators would be a lot cheaper than replacing the ULN - 2003! Anyone like to comment or tackle the design or parts for this board? Let's kick it around a little! Eric - AA4SW
Re: [Flexradio] Frequency stability
Guy This is a copy of the last message in a previous go around. Tom, Steve, John, Jim: You want to throw some glue on the Reflock II Rockwell-Jupiter and put us out of our SDR stability misery, now that the II is available!? (smile). This is still on my projects mentoring list! Whats new on the SDR-1000 accessory board mentioned? Eric AA4SW ** All -- Just FYI, TAPR is working not only on the Reflock II, which can phase lock virtually any oscillator with a DC control voltage to either another frequency source, or to a 1pps from a GPS, but also an auxiliary board specifically designed to work with the SDR1000. It will provide a low-phse-noise 100MHz oscillator as well as an optional 10MHz TCXO to serve as reference (if you have a 1pps source, or other frequency standard, you can use that instead). The Reflock II will be shipping within a few weeks (we hope to have them for sale at the ARRL/TAPR Digital Communications Conference in Santa Ana, CA on Sep. 23-25). The SDR-1000 accessory board is just going into prototype but it's a pretty straightforward project so hopefully won't take too long to get ready for production. 73, John Jim Lux wrote: At 05:53 PM 9/6/2005, ecellison wrote: Jim I knew i could bait you! (smile). I am sort of 'gobbled up' by this precision thing! I do have my GPS receiver and am ready for the 1 part to the -13 (give or take a couple of exponents!). Can we take the 200 mhz standard out of the SDR 1000 as is? Actually I visit WWV frequently with the phase display, from 20 meters, where I been operating, and am actually pretty pleased with the long term accuracy of the radio. Course I fall asleep and leave it on. Eric You can skin that cat a number of ways. One way: pick off a sample of the 200 MHz and run it into a suitable divider/counter widget (like the one Brooke Shera described a few years back). Adjust in software Second way: Get a 200 MHz source that has a steering input and use it, instead of the 10 MHz source in a Z8301 type unit (or Brooke Shera's board). You could drive a divide by 20 with the 200 MHz source and use it in a system designed for 10 MHz unchanged. Third way: Get a high quality 200 MHz phase locked source and lock it to your 10 MHz source. ( you might be able to do this with an HP 8640..and used 8640s are cheaper than brand new 200 MHz phase locked sources) Fourth way: Measure the DDS output frequency against the 1pps or the 10 MHz, and calculate from there. You could either calculate a correction, and retune the DDS (but that might screw up the spur minimization techniques), or feed that into the IF processing in the software. Fifth way: Generate a comb from your stable reference, making sure that the comb spans the frequency bands you'll tune over. In software, find the comb, subtract it out, and use it to calibrate the rest. This is like using a crystal marker generator to calibrate your analog dial. The latter is what I'm doing at work, and I'll have a publically releasable descriptionof the details in a month or so. Suffice it to say today that we calibrate an arbitrary number of free running SDR1Ks and their PC sound cards to several ppb, including phase, especially if temperatures are reasonably stable. James Lux, P.E. ** From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Guy Atkins Sent: Sunday, November 20, 2005 12:45 AM To: FlexRadio@flex-radio.biz Subject: Re: [Flexradio] Frequency stability This site, which I've had bookmarked for a long time, offers low-priced 10 Mhz frequency standards for homebrewers: http://www.aade.com/ AADE offers nice little digital frequency displays, too, for old-tech radios. The firm is just a few miles from me, but I don't know if it's an actual storefront or a cottage industry run out of an amateur operator's home. Guy Atkins Puyallup, WA -Original Message- From: Ross [mailto:[EMAIL PROTECTED] Sent: Saturday, November 19, 2005 5:16 PM To: FlexRadio@flex-radio.biz Subject: [Flexradio] Frequency stability Bob,(and others) Would making up a 10mhz refence standard and usingGPS based timing, improve the frequency stability of the SDR1000. If so, suggestions please as to where to obtain or build up a precision standard. Thanks Ross ZL1WN
Re: [Flexradio] RFC - Poor Man's Universal Controller Board
All, I used Dale, N0XAS's, Univeral Keying Adapter for my Amp keying scheme. This little board uses an optically isolated,MOSFET solid-state relay part # G2-1A03 as the interface to the amplifier with the following specs; 1) Keys solid state, grid block or cathode keyed amplifiers or transmitters up to 400V AC or DC 2) Optical isolation between rig and key input 3) Self contained and low voltage power requirement 4) Compact size ideal for integration into other equipment For our proposed use, the only other component required, besides the optically isolated MOSFET chip, is a current limiting resistor in the range of 270 - 500 ohms for use with the 5V DC power source available from the SDR radio's X-2 connector pin 14. The optically isolated MOSFET chips input is driven directly from X-2 pin 7. If we wished, we could include on the Poor Man's Universal controller board (PMUCB) a group of these same optically isolated MOSFET chips for protecting X-2 control lines, pins 1-6. If the isolators are not required we could have pads or headers to bypass the optically isolated MOSFET chips and terminate at a 6 or 10 pin Berg connector as suggested by Eric2. It would be my desire to utilize 1/8 phone jacks mounted on the PMUCB for a foot switch or hand switch for keying the SDR via X-2 pin10 PTT input. I would like to thank Eric2 for making this proposal on the email reflector. We had discussed this subject prior to the Belize DXpedition trip on Teamspeak, and unfortunately he suffered an SDR radio component failure as a result of trying to connect a relay in an amplifier directly into the radio on x2-7 without any buffering. I believe now is the time for this supplemental SDR radio interface kit. We are all pleased with the Delta-44 breakout box replacement that Tony designed and had circuit boards manufactured for. And for which Eric2 purchased all of the components and dry assembled the entire kit to make available to all of us SDR-1000 radio owners. I don't know if it was ever verbalized by the SDR Radio owners community but I wish to thank Eric2 and Tony for a job extremely well done! Thanks, Wally - M0ZAZ. At 05:55 AM 11/20/2005 -0500, you wrote: Larry Thanks, I have never had and amp so really don't know the keying schemes. I would imagine that most are quite benign, however, a little relay in x2-7 would put an end to the question of spikes, voltage and current. Also 5V at 50 mils is available for the relay. Most feet switches or hand switches have all be 1/4 inch phone jacks, and although everyone hates the 1/8 inch jacks, the 1/4 is a little large to put on a self supporting mini circuit board. If a little board is proposed, it does make sense to make the other pins available on a header. Lemme know what you think. I think we can design the board ourselves, however Tony said he could whip it out. I surely would be less expensive then ruining the chip in the raid, and rival what users can do by jury rigging a 15 pin connector as I did for the foot switch. Eric -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Saturday, November 19, 2005 11:45 PM To: ecellison; FlexRadio@flex-radio.biz Subject: Re: [Flexradio] RFC - Poor Man's Universal Controller Board E^2, I'll give it a runthrough and see what should be on a little board to isolate the big bad world from the delicate innards of the ULN 2003. What I did for X2-7 was put a diode cross the relay coil in my Drake L-4 amp as that coil puts out over 400 V on the back voltage. The coil is driven by a 30 VDC supply and draws 50 MA when the transmit line is grounded. What else do people have in amps? Control line specs? I know there are already several widgit boxes on the market for the amp control interface. We need to have the rest of the input/outputs protected and incorporate the amp control in one plugin. 73, Larry K2LT drakerepair.com 800-687-9161 From: ecellison [EMAIL PROTECTED] Date: 2005/11/20 Sun AM 01:59:34 WET To: FlexRadio@flex-radio.biz Subject: [Flexradio] RFC - Poor Man's Universal Controller Board Folks I think I blew the ULN 2003 open collector chip out of my radio during the Belize DXpedition by trying to connect a relay in an amplifier directly into the radio on x2-7 without any buffering. Perhaps a spike or surge. Dunno. But it brings back to mind a project I suggested to Tony - KB9YIG who has done a fantastic job designing and refining kits for the SDR-1000 and is currently totally immersed in the SoftRock40 SDR. At one time I had suggested a Poor Man's UCB to connect dedicated and open pins to the X2 15 pin connector. It was shelved and deemed not necessary since users can plug just about anything into the X2 connector and experiment. As a result of my experience, I'd like to 'throw' out an idea to create an inexpensive PC Board to protect the X2-7 output to control Amps etc, with a 5 v relay and provide jack for a cold
Re: [Flexradio] Frequency stability
Hi Eric -- Yes, the Reflock II is now shipping as a kit, though it requires fairly fine-pitch SMD soldering. We'll have an assembled and tested version available as soon as we can get the contract manufacturer lined up. I've done some tests of the Reflock II using a GPS 1pps steering an eBay surplus TCXO, and the performance is quite good. It's not the equal of a more sophisticated GPS disciplined oscillator like the surplus Z3801A, but it holds within parts in 10e9 (e.g., about +/-25Hz at 10GHz). The only downside is that the frequency error isn't a slow ramp, but rather looks like noise with a peak-to-peak period of a few seconds. At HF or even multiplied up to VHF, that's not going to be noticeable. But it bugs me, and we're working to see if there's a way to fix it. NOTE: I haven't measured to see if this effect occurs when using an oscillator, rather than GPS, as the reference. I strongly suspect that you won't see this when locking to an oscillator, because the loop design is very different in that case. TAPR is planning to offer a daughterboard to go along with the Reflock II that will provide a good quality 10MHz oscillator to serve as the reference, and a low jitter VCXO running at 100MHz to drive the SDR-1000. You'll be able to bypass the 10MHz oscillator and use your own, or use GPS, if you'd like. I'm not certain just when the daughterboard will be available, but I know that Steve Bible, N7HPR, has been working on it. (By the way -- the same daughterboard, with a different VCXO, will also drive the Matt Ettus USRP software radio board.) 73, John ecellison said the following on 11/20/2005 06:24 AM: We have gone around in circles a number of times on this subject and it is still on my 'project mentoring' list of things to design collectivly. Depending on how much we have to spend, the best bet looks like TAPR Reflock 2 which has finally been offered as a kit for about $110 and can be slaved to GPS or a high accuracy 10 mhz TC(VC?)XO and produce accurate 100 - 250 mhz standard avoiding the phase shift by multiplying up from 10 mhz. We have not hashed this out lately. http://www.tapr.org/kits_reflock_ii.html?PHPSESSID=f42b43a04fcded6a42ced6193 4840545 Perhaps John N8UR can comment on a complete design using the Reflock-2, and 1 pps GPS.
Re: [Flexradio] RFC - Poor Man's Universal Controller Board
Wally Thanks for the input, and I would definitely like to persue this as a project. Iffn you got a pencil, how about a sketch or something since you have already jumped on it and have the parts details. A kit should be pretty simple to do. How are you at ExpressPCB? Larry, sorry we don't have something for you at the moment! They do make 5 volt relays I saw them from DigiKey. Onea dem and a diode should get you in business. Eric2 -Original Message- From: Larry Loen [mailto:[EMAIL PROTECTED] Sent: Sunday, November 20, 2005 4:12 AM To: Wallace Watson Cc: ecellison; FlexRadio@flex-radio.biz Subject: Re: [Flexradio] RFC - Poor Man's Universal Controller Board Wallace Watson wrote: All, I used Dale, N0XAS's, Univeral Keying Adapter for my Amp keying scheme. This little board uses an optically isolated,MOSFET solid-state relay part # G2-1A03 as the interface to the amplifier with the following specs; 1) Keys solid state, grid block or cathode keyed amplifiers or transmitters up to 400V AC or DC 2) Optical isolation between rig and key input 3) Self contained and low voltage power requirement 4) Compact size ideal for integration into other equipment For our proposed use, the only other component required, besides the optically isolated MOSFET chip, is a current limiting resistor in the range of 270 - 500 ohms for use with the 5V DC power source available from the SDR radio's X-2 connector pin 14. The optically isolated MOSFET chips input is driven directly from X-2 pin 7. If we wished, we could include on the Poor Man's Universal controller board (PMUCB) a group of these same optically isolated MOSFET chips for protecting X-2 control lines, pins 1-6. If the isolators are not required we could have pads or headers to bypass the optically isolated MOSFET chips and terminate at a 6 or 10 pin Berg connector as suggested by Eric2. It would be my desire to utilize 1/8 phone jacks mounted on the PMUCB for a foot switch or hand switch for keying the SDR via X-2 pin10 PTT input. I would like to thank Eric2 for making this proposal on the email reflector. We had discussed this subject prior to the Belize DXpedition trip on Teamspeak, and unfortunately he suffered an SDR radio component failure as a result of trying to connect a relay in an amplifier directly into the radio on x2-7 without any buffering. I believe now is the time for this supplemental SDR radio interface kit. We are all pleased with the Delta-44 breakout box replacement that Tony designed and had circuit boards manufactured for. And for which Eric2 purchased all of the components and dry assembled the entire kit to make available to all of us SDR-1000 radio owners. I don't know if it was ever verbalized by the SDR Radio owners community but I wish to thank Eric2 and Tony for a job extremely well done! Thanks, Wally - M0ZAZ. At 05:55 AM 11/20/2005 -0500, you wrote: I have this problem in real-time. I am, right now, trying to work out the details of keying a Harris Miltary Surplus Amplfier. It is a very interesting device, having apparently been used all over the government (military, especially) over the last 20 or 30 years. Not least of the problems is figuring out how to safely hook up a rig like the SDR 1000 to it. I'm going to have to do what I'm least good at -- a little homebrewing -- at the moment it would be most dangerous to our favorite transmitter. And, of course, I'd like to get it done before CQ WW this next weekend, so I don't have forever, at least not if I want the amp for the contest. The more obvious schemes, using readily available parts, would involve using twelve volts to trigger 110v AC relays. At least, the T/R HF switch I currently have is triggered off of 110, but obviously, I don't want to switch that directly. The most readily available scheme would be a 12v triggered AC relay which would then be hooked to the T/R antenna switch, itself switched off of 110v. But, ultimately, if I want to trigger this from the SDR itself, I'm going to need optical isolation or open collectors or something so I can translate the available voltages off the back of the SDR to the 12v that my current scheme, at least, will need. Maybe there are 5v triggered relays out there, but this is what I have for now. I'm going to get a hand from Terry, W0VB, who really understands this stuff 100 fold better than I do. But, at least at the present, this is what I'm expecting to do. A supplemental SDR interface board that made it easy to do these sorts of things, especially if it protected the rig against most errors and stupidity, would be a real boon to me, right now, today. Larry WO0Z
Re: [Flexradio] Teamspeak Forum Audio - 11-19-05
Thanks for the reply, Eric. The WolfsonADC looks like a nice part. Is the initial design only to be a stereo ADC-to-USB, rather than both ADCs DACs? I have no experience connecting audio to USB, and so I'm wondering... if DACs are planned, I'm curious how one locks the DAC clocks to the incoming USB audio stream (the Altera parts have PLL's - but their utility doesn't go too far). Does the same issue exist if one only performs the ADC function? Thanks, - Jeff, WA6AHL -Original Message-From: ecellison [mailto:[EMAIL PROTECTED]Sent: Saturday, November 19, 2005 3:25 PMTo: 'Jeff Anderson'; FlexRadio@flex-radio.bizSubject: RE: [Flexradio] Teamspeak Forum Audio - 11-19-05 Jeff Well, I know that Phil N8VB is working with an Altera and from his previous post has a Xylo board. Phil VK6APH has also purchased a Xylo board as have I. My knowledge is minimal however, the board was inexpensive and it would appear that this kit and the sample and supporting C and HDL code would form the basis for a great glue chip for many projects which we have collectively discussed for the SDR-1000 over the past year. Phil is designing an entire SDR based on FPGA. Early this year, we had 3 users interested in a PIC-4550 with USB, and we all bought boards, C-compilers, and protokits. but that project is stalled, for a number of reasons, none the least of which was a pretty buggy C compiler IDE from FED. Also streaming audio back through the USB port was a bit too slow in serial. A lack of good understanding of audio USB interface. Etc. I think the primary excitement last February was the prospect of eliminating the need for a sound card. We did some research and rejected almost all Codec chips at the time, and found the very inexpensive Wolfson 8785 ADC chip which has an I2S interface, for minimal parts and connections, 192, khz, 24 bit, stereo input, thd 102 SNR 111 http://www.wolfsonmicro.com/uploads/documents/WM8785.pdf They also have a nice DAC chip in the same type mold. At the same time and after, we have discussed a number of other projects which would be ideal to nail into an embedded system. High accuracy/stability time base using a 1 pps time source from GPS receiver. Integrated full function Keyer with sidetone. DDS replacement PLL or NCO. TCP/IP for remoting of the SDR-1000 Replacing the switch functions on the PIO board over USB rather than parallel port. External Main tuning knob(s) and other handy buttons for the folks who quiver and shake in Knob Withdrawl! Complete replacement of the PIO board. I am sure I am forgetting things we discussed as potential for embedded system assist for the SDR 1000, and havent thought of others. I think a project like this needs both folks (as many as we can get) who have experience with this embedded system, taking the lead, or suggesting resources methodology and code. Then others willing to support and test code etc. Thanks for speaking up! This is worthy of discussion. Eric AA4SW From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Jeff AndersonSent: Saturday, November 19, 2005 3:54 PMTo: FlexRadio@flex-radio.bizSubject: Re: [Flexradio] Teamspeak Forum Audio - 11-19-05 Regarding Altera experience - I'm currentlywriting Verilog codefor an Altera Cyclone II part (EP2C5) that, amongst other functions, interaces to some AKM stereo codecs. What's the planned Xylo project? - Jeff, WA6AHL -Original Message-From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of ecellisonSent: Friday, November 18, 2005 8:29 PMTo: FlexRadio@flex-radio.bizSubject: [Flexradio] Teamspeak Forum Audio - 11-19-05 Folks (and Phil N8VB) Sorry have been falling down on the job! I will post last two weeks forum audio after tonights audio. Came back from Belize thinking I was still on vacation (smile). Actually with broken radio and broken computer. The computer has all my tools for doing just about everything. Got a bit Crushed in its Aria enclosure, on its way back from Belize and now has an intermittent, sudden shutdown problem! In any case have fallen back to a laptop and installed the audio stuff I use for teamspeak. Tonights audio: Phil departing for South Australia (wherever that is! I thought he WAS in South Australia!!). Winked and blinked his green light, since he had to go. He has been working with the Xylo Altera FPGA board, and has gotten it interfaced with the Wolfson AD chip and configured. Next week he will be working on streaming stuff from the chip back through USB to the computer. Since he mentioned this
Re: [Flexradio] Frequency stability
John Thanks! The daughterboard sounds ideal for what a lot of us want for the SDR-1000. Is the frequency error you mentioned possibly due to the introduced small error in the GPS timebases? I know that in the QST article (can't remember the name) that there was a cyclic and random error from the satellites. Although I seem to recall that it was temperature changes in the shack where he was testing. If it's predictable, probably can be eliminated in software. I really like the fact that it has an I2C interface, since there are a few of us just getting started with the Cyclone FPGA in the Xylo board. One of the ideas was to use an NCO but with I2C we can talk with the Refloc II on the same bus, and the Reflock II is a jewel in the center of the crown of getting really accurate with the SDR-1000! http://www.fpga4fun.com/board_Xylo.html I included Steve, Tim and Tom in another message, since they were major contributors in the first discussions. I think this go around should produce the ideas to glue it all together into a working device. I'm a little shaky on the fine pitch stuff myself and may wait to order the Reflock until you have an assembled kit. Thanks to you and Steve and others for this fine production from TAPR. Gess you can sit back and relax now that someone else is in the saddle! (smile) Fat chance! Eric2 -Original Message- From: John Ackermann N8UR [mailto:[EMAIL PROTECTED] Sent: Sunday, November 20, 2005 9:10 AM To: ecellison Cc: 'Guy Atkins'; FlexRadio@flex-radio.biz; Steven Bible Subject: Re: [Flexradio] Frequency stability Hi Eric -- Yes, the Reflock II is now shipping as a kit, though it requires fairly fine-pitch SMD soldering. We'll have an assembled and tested version available as soon as we can get the contract manufacturer lined up. I've done some tests of the Reflock II using a GPS 1pps steering an eBay surplus TCXO, and the performance is quite good. It's not the equal of a more sophisticated GPS disciplined oscillator like the surplus Z3801A, but it holds within parts in 10e9 (e.g., about +/-25Hz at 10GHz). The only downside is that the frequency error isn't a slow ramp, but rather looks like noise with a peak-to-peak period of a few seconds. At HF or even multiplied up to VHF, that's not going to be noticeable. But it bugs me, and we're working to see if there's a way to fix it. NOTE: I haven't measured to see if this effect occurs when using an oscillator, rather than GPS, as the reference. I strongly suspect that you won't see this when locking to an oscillator, because the loop design is very different in that case. TAPR is planning to offer a daughterboard to go along with the Reflock II that will provide a good quality 10MHz oscillator to serve as the reference, and a low jitter VCXO running at 100MHz to drive the SDR-1000. You'll be able to bypass the 10MHz oscillator and use your own, or use GPS, if you'd like. I'm not certain just when the daughterboard will be available, but I know that Steve Bible, N7HPR, has been working on it. (By the way -- the same daughterboard, with a different VCXO, will also drive the Matt Ettus USRP software radio board.) 73, John ecellison said the following on 11/20/2005 06:24 AM: We have gone around in circles a number of times on this subject and it is still on my 'project mentoring' list of things to design collectivly. Depending on how much we have to spend, the best bet looks like TAPR Reflock 2 which has finally been offered as a kit for about $110 and can be slaved to GPS or a high accuracy 10 mhz TC(VC?)XO and produce accurate 100 - 250 mhz standard avoiding the phase shift by multiplying up from 10 mhz. We have not hashed this out lately. http://www.tapr.org/kits_reflock_ii.html?PHPSESSID=f42b43a04fcded6a42ced6193 4840545 Perhaps John N8UR can comment on a complete design using the Reflock-2, and 1 pps GPS.
Re: [Flexradio] Frequency stability
At 05:15 PM 11/19/2005, Ross wrote: Bob, (and others) Would making up a 10mhz refence standard and using GPS based timing, improve the frequency stability of the SDR1000. If so, suggestions please as to where to obtain or build up a precision standard. There's been a bit of discussion about this in the archives, however, it's sort of a pain to find it. One can buy used GPS disciplined standards such as the HP Z3801. If that's in your budget, it's the all around easiest way, becuase all the icky details of integration, control loops, etc. have all been taken care of. For a while, these were $250, but I haven't seen them that cheap recently. And, I have no idea what the market is like in ZL-land... They were used extensively in cellsites and then superseded, so they might be just as cheap there. There's also Brooke Shera's little board which uses the 1pps from any GPS receiver to discipline a 10 MHz VCXO. Google and you'll find it. You'd need to scrounge up a decent VCXO, as well. If you're not power/mass constrained, you can probably find a surplus (or new) ovenized oscillator to use as a frequency standard. HP/Agilent makes zillions of them, because they sit in practically every piece of RF test gear. Wenzel is another good brand to look for. I'd imagine $100 used will turn one up. Brand new, a few hundred bucks. BUT, what you probably really need is just to calibrate your radio, not to actually generate a precision 10 MHz phase/frequency reference. That is, you don't really care what frequency the oscillator on your radio is running at, as long as the software knows what it is, so that when you enter a particular frequency on the dial, the DDS gets programmed appropriately, and the software demod tunes correctly. James Lux, P.E. Spacecraft Radio Frequency Subsystems Group Flight Communications Systems Section Jet Propulsion Laboratory, Mail Stop 161-213 4800 Oak Grove Drive Pasadena CA 91109 tel: (818)354-2075 fax: (818)393-6875
Re: [Flexradio] Frequency stability
Hi Eric -- The frequency wander seems to be the result of the Reflock II steering step size. Since Luis hasn't yet published the VHDL code that drives the Reflock, we're only guessing, but it appears that the noise occurs when the frequency is around the midpoint between two steering steps. The result is that the output bounces between the upper and lower steps. I suspect this because sometimes the thing will quiet way down and have an order of magnitude better stability, then it will start wobbling again. If this is what's happening, it should be possible to modify the code or the hardware to improve this characteristic. The GPS signal does wander around somewhat, and on top of that the receivers all contribute their own noise in the 50-100ns range. That's why you need to average the GPS signal over quite a time period (1000 seconds or more) to get really good results. However, for use at HF or VHF you can get away with shorter averaging times. Again, we don't know quite what is in Luis' code, but I suspect he's averaging over 60 seconds or so. 73, John ecellison said the following on 11/20/2005 09:44 AM: John Thanks! The daughterboard sounds ideal for what a lot of us want for the SDR-1000. Is the frequency error you mentioned possibly due to the introduced small error in the GPS timebases? I know that in the QST article (can't remember the name) that there was a cyclic and random error from the satellites. Although I seem to recall that it was temperature changes in the shack where he was testing. If it's predictable, probably can be eliminated in software. I really like the fact that it has an I2C interface, since there are a few of us just getting started with the Cyclone FPGA in the Xylo board. One of the ideas was to use an NCO but with I2C we can talk with the Refloc II on the same bus, and the Reflock II is a jewel in the center of the crown of getting really accurate with the SDR-1000! http://www.fpga4fun.com/board_Xylo.html I included Steve, Tim and Tom in another message, since they were major contributors in the first discussions. I think this go around should produce the ideas to glue it all together into a working device. I'm a little shaky on the fine pitch stuff myself and may wait to order the Reflock until you have an assembled kit. Thanks to you and Steve and others for this fine production from TAPR. Gess you can sit back and relax now that someone else is in the saddle! (smile) Fat chance! Eric2 -Original Message- From: John Ackermann N8UR [mailto:[EMAIL PROTECTED] Sent: Sunday, November 20, 2005 9:10 AM To: ecellison Cc: 'Guy Atkins'; FlexRadio@flex-radio.biz; Steven Bible Subject: Re: [Flexradio] Frequency stability Hi Eric -- Yes, the Reflock II is now shipping as a kit, though it requires fairly fine-pitch SMD soldering. We'll have an assembled and tested version available as soon as we can get the contract manufacturer lined up. I've done some tests of the Reflock II using a GPS 1pps steering an eBay surplus TCXO, and the performance is quite good. It's not the equal of a more sophisticated GPS disciplined oscillator like the surplus Z3801A, but it holds within parts in 10e9 (e.g., about +/-25Hz at 10GHz). The only downside is that the frequency error isn't a slow ramp, but rather looks like noise with a peak-to-peak period of a few seconds. At HF or even multiplied up to VHF, that's not going to be noticeable. But it bugs me, and we're working to see if there's a way to fix it. NOTE: I haven't measured to see if this effect occurs when using an oscillator, rather than GPS, as the reference. I strongly suspect that you won't see this when locking to an oscillator, because the loop design is very different in that case. TAPR is planning to offer a daughterboard to go along with the Reflock II that will provide a good quality 10MHz oscillator to serve as the reference, and a low jitter VCXO running at 100MHz to drive the SDR-1000. You'll be able to bypass the 10MHz oscillator and use your own, or use GPS, if you'd like. I'm not certain just when the daughterboard will be available, but I know that Steve Bible, N7HPR, has been working on it. (By the way -- the same daughterboard, with a different VCXO, will also drive the Matt Ettus USRP software radio board.) 73, John ecellison said the following on 11/20/2005 06:24 AM: We have gone around in circles a number of times on this subject and it is still on my 'project mentoring' list of things to design collectivly. Depending on how much we have to spend, the best bet looks like TAPR Reflock 2 which has finally been offered as a kit for about $110 and can be slaved to GPS or a high accuracy 10 mhz TC(VC?)XO and produce accurate 100 - 250 mhz standard avoiding the phase shift by multiplying up from 10 mhz. We have not hashed this out lately.
Re: [Flexradio] Teamspeak Forum Audio - 11-19-05
Jeff I really need Phil VK6APH to comment, and maybe Phil N8VB will chime in on this thread. Phil was going to eliminate the DAC by using the PIC to do the DAC for transmit. If I remember, he did have that working. I think it was 10 bit which was enough for SSB but Digi modes were in question. The feeling was that we could stream the digital stream back through the USB. I am having difficulty remembering exactly what Phil1, (here we go again(smile)) VK6APH had proposed. Phil1 is on a trip to South Australia so dunno when he will be available for comment. I do know he will be very anxious to chat with you! Hopefully we can get you and some others with FPGA experience to help us along! Phil Covington N8VB is designing an entire SDR around an Altera FPGA (and other wonderful things!) http://www.philcovington.com/ See HPSDR Board picts at the top of his page. Thanks Eric From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Jeff Anderson Sent: Sunday, November 20, 2005 9:20 AM To: FlexRadio@flex-radio.biz Subject: Re: [Flexradio] Teamspeak Forum Audio - 11-19-05 Thanks for the reply, Eric. The WolfsonADC looks like a nice part. Is the initial design only to be a stereo ADC-to-USB, rather than both ADCs DACs? I have no experience connecting audio to USB, and so I'm wondering... if DACs are planned, I'm curious how one locks the DAC clocks to the incoming USB audio stream (the Altera parts have PLL's - but their utility doesn't go too far). Does the same issue exist if one only performs the ADC function? Thanks, - Jeff, WA6AHL -Original Message- From: ecellison [mailto:[EMAIL PROTECTED] Sent: Saturday, November 19, 2005 3:25 PM To: 'Jeff Anderson'; FlexRadio@flex-radio.biz Subject: RE: [Flexradio] Teamspeak Forum Audio - 11-19-05 Jeff Well, I know that Phil N8VB is working with an Altera and from his previous post has a Xylo board. Phil VK6APH has also purchased a Xylo board as have I. My knowledge is minimal however, the board was inexpensive and it would appear that this kit and the sample and supporting C and HDL code would form the basis for a great glue chip for many projects which we have collectively discussed for the SDR-1000 over the past year. Phil is designing an entire SDR based on FPGA. Early this year, we had 3 users interested in a PIC-4550 with USB, and we all bought boards, C-compilers, and protokits. but that project is stalled, for a number of reasons, none the least of which was a pretty buggy C compiler IDE from FED. Also streaming audio back through the USB port was a bit too slow in serial. A lack of good understanding of audio USB interface. Etc. I think the primary excitement last February was the prospect of eliminating the need for a sound card. We did some research and rejected almost all Codec chips at the time, and found the very inexpensive Wolfson 8785 ADC chip which has an I2S interface, for minimal parts and connections, 192, khz, 24 bit, stereo input, thd 102 SNR 111 http://www.wolfsonmicro.com/uploads/documents/WM8785.pdf They also have a nice DAC chip in the same type mold. At the same time and after, we have discussed a number of other projects which would be ideal to nail into an embedded system. High accuracy/stability time base using a 1 pps time source from GPS receiver. Integrated full function Keyer with sidetone. DDS replacement PLL or NCO. TCP/IP for remoting of the SDR-1000 Replacing the switch functions on the PIO board over USB rather than parallel port. External Main tuning knob(s) and other handy buttons for the folks who quiver and shake in Knob Withdrawl! Complete replacement of the PIO board. I am sure I am forgetting things we discussed as potential for embedded system assist for the SDR 1000, and havent thought of others. I think a project like this needs both folks (as many as we can get) who have experience with this embedded system, taking the lead, or suggesting resources methodology and code. Then others willing to support and test code etc. Thanks for speaking up! This is worthy of discussion. Eric AA4SW From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Jeff Anderson Sent: Saturday, November 19, 2005 3:54 PM To: FlexRadio@flex-radio.biz Subject: Re: [Flexradio] Teamspeak Forum Audio - 11-19-05 Regarding Altera experience - I'm currentlywriting Verilog codefor an Altera Cyclone II part (EP2C5) that, amongst other functions, interaces to some AKM stereo codecs. What's the planned Xylo project? - Jeff, WA6AHL -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of ecellison Sent: Friday, November 18, 2005 8:29 PM To: FlexRadio@flex-radio.biz Subject: [Flexradio] Teamspeak Forum Audio - 11-19-05 Folks (and Phil N8VB) Sorry have been falling down on the job! I will post last two weeks forum audio
Re: [Flexradio] Teamspeak Forum Audio - 11-19-05
Hi Eric, On the D/A part of the equation we need to look at whether we could use PWM output from the FPGA into a LPF. I have done this for audio output into a speaker (with an amp in between), but we would have to see if it would give use the dynamic range we would require for the I and Q outputs to the QSE. I think this should work... Using two pins for PWM output from the FPGA would eliminate the need for an external stereo D/A. Phil N8VB On 11/20/05, ecellison [EMAIL PROTECTED] wrote: Jeff I really need Phil – VK6APH to comment, and maybe Phil – N8VB will chime in on this thread. Phil was going to eliminate the DAC by using the PIC to do the DAC for transmit. If I remember, he did have that working. I think it was 10 bit which was enough for SSB but Digi modes were in question. The feeling was that we could stream the digital stream back through the USB. I am having difficulty remembering exactly what Phil1, (here we go again(smile)) VK6APH had proposed. Phil1 is on a trip to South Australia so dunno when he will be available for comment. I do know he will be very anxious to chat with you! Hopefully we can get you and some others with FPGA experience to help us along! Phil Covington N8VB is designing an entire SDR around an Altera FPGA (and other wonderful things!) http://www.philcovington.com/ See HPSDR Board picts at the top of his page. Thanks Eric
[Flexradio] amp pin out
OK..How is everyone wiring the amp control..what pin out? Bob
[Flexradio] Today's Net
Flex Gang, Looks like to me that the net won't happen today due to the SS Contest going on today.. We can try to meet on 17 , not as a net but just a discussion group.. Anyone have any ideals?? Thanks, Dudley WA5QPZ
Re: [Flexradio] Teamspeak Forum Audio - 11-19-05
At 09:19 AM 11/20/2005, Philip Covington wrote: Hi Eric, On the D/A part of the equation we need to look at whether we could use PWM output from the FPGA into a LPF. I have done this for audio output into a speaker (with an amp in between), but we would have to see if it would give use the dynamic range we would require for the I and Q outputs to the QSE. I think this should work... Using two pins for PWM output from the FPGA would eliminate the need for an external stereo D/A. Phil N8VB One might want to do some analysis before committing to a fairly low res D/A on this kind of thing. While for single tones, you can do very, very well with relatively few bits, when you start having real signals with many tones, the required performance might increase. Think in terms of needing to keep that 90 degree phase shift at all frequencies for good image rejection and carrier suppression. There's also the peak/average problem with complex signals (all the phases happen to line up just right sometimes), most commonly noted in things like COFDM (where the usual strategy is just to let it clip in those 0.1% of the cases where it happens). Jim, W6RMK
[Flexradio] Observations on Image Rejection...
My SDR1K arrived two weeks ago, and I've spent the last week playing with it and, in the process, have made a few observations regarding its performance and operation. Others may be interested in what I observed... First, I was surprised to observe that, after nulling the received image down to the noise floor, the image popped back up if I tuned off-frequency a bit. So I ran a few experiments: Experiment 1. Null the image at a given frequency, and then, with the receiver tuned to the null frequency (centered in the display) and without changing the receiver's frequency, change the generator's frequency. If re-nulling is required, note the new Phase and Gain values. I set my generator at 19 MHz and nulled the image at 19.02205 MHz (the spur reduction box must be *unselected*- otherwise, the image could be at some other frequency). Then, while monitoring 19.02205 MHz, I changed the frequency of my generator both above and below 19 MHz in 1 KHz steps. The results surprised me. As I moved the generator off of 19 MHz by *only* 1 KHz, the image returned, and it became larger and larger the further I moved the generator off frequency (by only a few KHz) in either direction. If I renulled the image manually (keeping the receiver at 19.02205 MHz), I had to change the phase by larger and larger amounts (and these were significant amounts!) as I moved the image further and further off frequency in either direction. Experiment 2. Null the image at a given frequency and note the Phase and Gain values. Shift the generator by 100 KHz and renull the image, using the same frequency offset to center the null in the display (22.05 KHz for my receiver - note that spur reduction must be unselected). Note the new Phase and Gain values. I set my generator at 19 MHz and nulled the image at 19.02205 MHz. Then I set my generator to 18.9 MHz and nulled the image at 18.92205 MHz, making sure that the image was properly centered on my display each time. Interestingly, the phase and gain settings were very close to each other for the two frequencies, and much closer to each other than the values I had measured in experiment 1, in which I moved the generator frequency by only 1 KHz, rather than 100 KHz. From the results of experiement 1, I'm guessing that the PowerSDR software phase-nulling algorithm does a simple time-delay shift when you adjust the phase control, to reduce the received spur. Adjusting a time-delay between the I Q channels will create a great null (into the noise floor) at that single audio frequency, but the null will immediately degrade as one moves off the nulled frequency, and I've measured it degrade by 20 dB (or more) worse at +/- 10 KHz (making the image rejection on the order of 50- 60 dB). Some other observations: 1. Slightly nudging or bumping the 3.5mm plug inserted into the SDR1K's To Line In connector can dramatically change the Receiver's image rejection, and it often does not return to its original value after the nudge. A more secure mechanical connection for this signal-pair (received I Q) is recommended. 2. Different Phase and Gain values are required whenever a filter band changes (e.g. if you hear relays click when changing frequencies), even if the frequency change is very small. 3. The Phase and Gain values required to null a signal can change significantly from one end of a filter band to the other (e.g. from 14.5 MHz to 21.5 MHz). 4. The image null can change significantly (20 dB) when changing the Preamp setting from Med (or High) to Low or Off. 5. Transmitter image rejection changes from band to band. Ideally, it would be nice to have independent settings for each band. In addition to these observations regarding Image Rejection, I also noticed that Carrier Suppression, when operating either USB or LSB, varied from band to band. I compared the amount of carrier observed when transmitting in AM to the amount of supressed carrier observed when transmitting DSB (measurements were all made using the SDR1K's QRP ouput fed, thru an attenuator, to an 8568B spectrum analyzer). On 40 meters carrier supression was on the order of 50 dB or better. On 20 it was 40 dB, and worse case it was 35 dB on 12 meters. I'm curious as to the cause of the varying of carrier supression vs. frequency. The fact that there's some carrier on sideband implies (to me) that there is a DC offset at the inputs of the transmit FST3253 (IC2 on the TRX board), which at first glance would seem surprising, given that the outputs of the driving op-amps are AC coupled. But there *is* a possible source of DC, which is the DC bias voltage aplied to T1.2. Perhaps there is a leakage problem with one or more of the 22 uF caps, or perhaps this voltage at T1.2, in combination with parasitics at IC2's inputs (and heaven knows what the 22 uF caps and the DRV135 outputs look like at 24.9 MHz) is somehow creating an offset? An interesting experiment might be to add a low-impedance path (at RF) from IC2's
Re: [Flexradio] Observations on Image Rejection...
I should add that, because carrier suppression varies with frequency, I doubt that it's simply an issue of capacitance leakage. Parasitics would be my bet. By the way - what's generally considered to be an acceptable level of carrier suppression when operating sideband? -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Sunday, November 20, 2005 11:55 AM To: Reflector Flex-Radio Subject: [Flexradio] Observations on Image Rejection... My SDR1K arrived two weeks ago, and I've spent the last week playing with it and, in the process, have made a few observations regarding its performance and operation. Others may be interested in what I observed... First, I was surprised to observe that, after nulling the received image down to the noise floor, the image popped back up if I tuned off-frequency a bit. So I ran a few experiments: Experiment 1. Null the image at a given frequency, and then, with the receiver tuned to the null frequency (centered in the display) and without changing the receiver's frequency, change the generator's frequency. If re-nulling is required, note the new Phase and Gain values. I set my generator at 19 MHz and nulled the image at 19.02205 MHz (the spur reduction box must be *unselected*- otherwise, the image could be at some other frequency). Then, while monitoring 19.02205 MHz, I changed the frequency of my generator both above and below 19 MHz in 1 KHz steps. The results surprised me. As I moved the generator off of 19 MHz by *only* 1 KHz, the image returned, and it became larger and larger the further I moved the generator off frequency (by only a few KHz) in either direction. If I renulled the image manually (keeping the receiver at 19.02205 MHz), I had to change the phase by larger and larger amounts (and these were significant amounts!) as I moved the image further and further off frequency in either direction. Experiment 2. Null the image at a given frequency and note the Phase and Gain values. Shift the generator by 100 KHz and renull the image, using the same frequency offset to center the null in the display (22.05 KHz for my receiver - note that spur reduction must be unselected). Note the new Phase and Gain values. I set my generator at 19 MHz and nulled the image at 19.02205 MHz. Then I set my generator to 18.9 MHz and nulled the image at 18.92205 MHz, making sure that the image was properly centered on my display each time. Interestingly, the phase and gain settings were very close to each other for the two frequencies, and much closer to each other than the values I had measured in experiment 1, in which I moved the generator frequency by only 1 KHz, rather than 100 KHz. From the results of experiement 1, I'm guessing that the PowerSDR software phase-nulling algorithm does a simple time-delay shift when you adjust the phase control, to reduce the received spur. Adjusting a time-delay between the I Q channels will create a great null (into the noise floor) at that single audio frequency, but the null will immediately degrade as one moves off the nulled frequency, and I've measured it degrade by 20 dB (or more) worse at +/- 10 KHz (making the image rejection on the order of 50- 60 dB). Some other observations: 1. Slightly nudging or bumping the 3.5mm plug inserted into the SDR1K's To Line In connector can dramatically change the Receiver's image rejection, and it often does not return to its original value after the nudge. A more secure mechanical connection for this signal-pair (received I Q) is recommended. 2. Different Phase and Gain values are required whenever a filter band changes (e.g. if you hear relays click when changing frequencies), even if the frequency change is very small. 3. The Phase and Gain values required to null a signal can change significantly from one end of a filter band to the other (e.g. from 14.5 MHz to 21.5 MHz). 4. The image null can change significantly (20 dB) when changing the Preamp setting from Med (or High) to Low or Off. 5. Transmitter image rejection changes from band to band. Ideally, it would be nice to have independent settings for each band. In addition to these observations regarding Image Rejection, I also noticed that Carrier Suppression, when operating either USB or LSB, varied from band to band. I compared the amount of carrier observed when transmitting in AM to the amount of supressed carrier observed when transmitting DSB (measurements were all made using the SDR1K's QRP ouput fed, thru an attenuator, to an 8568B spectrum analyzer). On 40 meters carrier supression was on the order of 50 dB or better. On 20 it was 40 dB, and worse case it was 35 dB on 12 meters. I'm curious as to the cause of the varying of carrier supression vs. frequency. The fact that there's some carrier on sideband implies (to me) that there is a DC offset at the inputs of the
Re: [Flexradio] Observations on Image Rejection...
At 12:03 PM 11/20/2005, Jeff Anderson wrote: I should add that, because carrier suppression varies with frequency, I doubt that it's simply an issue of capacitance leakage. Parasitics would be my bet. By the way - what's generally considered to be an acceptable level of carrier suppression when operating sideband? Wouldn't this fit under the spurious emissions requirements? 47cf97.307 has the details ...b) nothing that's out of band is acceptable.. so, if you're operating close to the band edge, and image rejection is poor, you could get bit. As a practical matter, if it's down in the thermal noise floor, it's hard to detect. ...c) must be as low as practicible ...d) can't be more than 50mW or -40dBc which ever is lower (except if Tx power is 5W, in which case it's -30dBc: which would be 5mW) this is for HF.. for 30MHz the limits are tighter. If you're radiating 100W (+50dBm),then the -40dBc will be tougher. Those of you running some more fire in the wire might have to watch the 50mW limit (1kW is +60dBm, and the 50mW limit is +17dBm, -43dBc) Jim, W6RMK
[Flexradio] Another digital program issue
Has anyone tried using the VAC with Hamscope? http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=4816 This is a very nice Free program and interfaces well with quite a few logging programs (using Logic 7 here). When I set the soundcard choice to: input: 2 IN Output: 1 OUT I get an error, Can't open soundcard and then says to maybe try different sampling rate. I tried to change them from the VAC tab on PWRSdr, but still would not work. Any help would be great as it's an excellent program. Tnx Greg AB7R
Re: [Flexradio] Observations on Image Rejection...
Jeff Anderson wrote: The results surprised me. As I moved the generator off of 19 MHz by *only* 1 KHz, the image returned, and it became larger and larger the further I moved the generator off frequency (by only a few KHz) in either direction. If I renulled the image manually (keeping the receiver at 19.02205 MHz), I had to change the phase by larger and larger amounts (and these were significant amounts!) as I moved the image further and further off frequency in either direction. Jeff, I know almost nothing about the SDR1K, but I want to report to you and to the group what I observed about one year ago when writing my program SDRadio. I had coded an amplitude and phase compensating routine which nulled beautifully the image response. The hardware used was an home made QSD mixer with 2 x ADG704. Then I received a couple of reports from users that told me that they had a behavior like that you report, i.e. a good null at a single frequency, then a progressive worsening moving away from that. Luckily one of them was a skilled guy, with good instrumentation, and what turned out was that the two channels of his sound card had a fixed time skew between them ! This of course caused that the phase imbalance changed with the frequency, making the image nulling possible just at a single spot. The solution was to implement not a phase correction, but an adjustable time delay between the channels, and this needed to write a fractional delay routine, as the differential delay value had to be adjusted to values lower than the sampling period. Apparently only cheap sound cards have this problem, but I learned a lesson then... 73 Alberto I2PHD
Re: [Flexradio] Another digital program issue
Found a workaround. Hamscope lets you choose which soundcard to use, but also has an option to choose the best matchwhich I think means the default card. When I changed to that it seemed to work OK. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of ab7r Sent: Sunday, November 20, 2005 1:28 PM To: Flexradio@flex-radio.biz Subject: [Flexradio] Another digital program issue Has anyone tried using the VAC with Hamscope? http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=4816 This is a very nice Free program and interfaces well with quite a few logging programs (using Logic 7 here). When I set the soundcard choice to: input: 2 IN Output: 1 OUT I get an error, Can't open soundcard and then says to maybe try different sampling rate. I tried to change them from the VAC tab on PWRSdr, but still would not work. Any help would be great as it's an excellent program. Tnx Greg AB7R ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz
[Flexradio] NEW SETUP..
Fellows.. A little help here please..I have the radio all setup and working..I need help as to the pin out for a amp on the plug on the back of the rig..Thanks Bob
Re: [Flexradio] NEW SETUP..
Bob, I have used 2 amps with my SDR1K, an old Icom IC-2KL and a Ameritron Al-1500. In both cases the key line is wired to the external control connector X2 using pins 7 and 15. Pin 7 is the preferred pin for amplifiers and pin 15 is ground. Note: You MUST enable pin 7 on the Setup/General/Options page. You should also set the X2 Delay. I have mine set at 30 msec. Pin 7 allows for sequential timing of the amplifier, ie, the amp keys first then the SDR, then when you unkey, the SDR unkeys followed by the amp. Saves from transmitting into nothing. The pinout is located on page 12 of the manual which you can download from the website. It is on the main page at the top. 73, Dale AA5XE Bob W5RG wrote: Fellows.. A little help here please..I have the radio all setup and working..I need help as to the pin out for a amp on the plug on the back of the rig..Thanks Bob ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz
Re: [Flexradio] RFC - Poor Man's Universal Controller Board
I think the Hamgadgets Universal Keying adapter provides the isolation we're looking for. I will ask. I think the small kits, that go together in about 25 minutes are about $16. Greg AB7R -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of ecellison Sent: Sunday, November 20, 2005 6:17 AM To: 'Larry Loen'; 'Wallace Watson' Cc: FlexRadio@flex-radio.biz Subject: Re: [Flexradio] RFC - Poor Man's Universal Controller Board Wally Thanks for the input, and I would definitely like to persue this as a project. Iffn you got a pencil, how about a sketch or something since you have already jumped on it and have the parts details. A kit should be pretty simple to do. How are you at ExpressPCB? Larry, sorry we don't have something for you at the moment! They do make 5 volt relays I saw them from DigiKey. Onea dem and a diode should get you in business. Eric2 -Original Message- From: Larry Loen [mailto:[EMAIL PROTECTED] Sent: Sunday, November 20, 2005 4:12 AM To: Wallace Watson Cc: ecellison; FlexRadio@flex-radio.biz Subject: Re: [Flexradio] RFC - Poor Man's Universal Controller Board Wallace Watson wrote: All, I used Dale, N0XAS's, Univeral Keying Adapter for my Amp keying scheme. This little board uses an optically isolated,MOSFET solid-state relay part # G2-1A03 as the interface to the amplifier with the following specs; 1) Keys solid state, grid block or cathode keyed amplifiers or transmitters up to 400V AC or DC 2) Optical isolation between rig and key input 3) Self contained and low voltage power requirement 4) Compact size ideal for integration into other equipment For our proposed use, the only other component required, besides the optically isolated MOSFET chip, is a current limiting resistor in the range of 270 - 500 ohms for use with the 5V DC power source available from the SDR radio's X-2 connector pin 14. The optically isolated MOSFET chips input is driven directly from X-2 pin 7. If we wished, we could include on the Poor Man's Universal controller board (PMUCB) a group of these same optically isolated MOSFET chips for protecting X-2 control lines, pins 1-6. If the isolators are not required we could have pads or headers to bypass the optically isolated MOSFET chips and terminate at a 6 or 10 pin Berg connector as suggested by Eric2. It would be my desire to utilize 1/8 phone jacks mounted on the PMUCB for a foot switch or hand switch for keying the SDR via X-2 pin10 PTT input. I would like to thank Eric2 for making this proposal on the email reflector. We had discussed this subject prior to the Belize DXpedition trip on Teamspeak, and unfortunately he suffered an SDR radio component failure as a result of trying to connect a relay in an amplifier directly into the radio on x2-7 without any buffering. I believe now is the time for this supplemental SDR radio interface kit. We are all pleased with the Delta-44 breakout box replacement that Tony designed and had circuit boards manufactured for. And for which Eric2 purchased all of the components and dry assembled the entire kit to make available to all of us SDR-1000 radio owners. I don't know if it was ever verbalized by the SDR Radio owners community but I wish to thank Eric2 and Tony for a job extremely well done! Thanks, Wally - M0ZAZ. At 05:55 AM 11/20/2005 -0500, you wrote: I have this problem in real-time. I am, right now, trying to work out the details of keying a Harris Miltary Surplus Amplfier. It is a very interesting device, having apparently been used all over the government (military, especially) over the last 20 or 30 years. Not least of the problems is figuring out how to safely hook up a rig like the SDR 1000 to it. I'm going to have to do what I'm least good at -- a little homebrewing -- at the moment it would be most dangerous to our favorite transmitter. And, of course, I'd like to get it done before CQ WW this next weekend, so I don't have forever, at least not if I want the amp for the contest. The more obvious schemes, using readily available parts, would involve using twelve volts to trigger 110v AC relays. At least, the T/R HF switch I currently have is triggered off of 110, but obviously, I don't want to switch that directly. The most readily available scheme would be a 12v triggered AC relay which would then be hooked to the T/R antenna switch, itself switched off of 110v. But, ultimately, if I want to trigger this from the SDR itself, I'm going to need optical isolation or open collectors or something so I can translate the available voltages off the back of the SDR to the 12v that my current scheme, at least, will need. Maybe there are 5v triggered relays out there, but this is what I have for now. I'm going to get a hand from Terry, W0VB, who really understands this stuff 100 fold better than I do. But, at least at the present, this is what I'm expecting to do. A supplemental SDR interface board that made it easy to do these sorts of
