Can’t seem to find anything on the web about this receiver. Sounds interesting. Can someone point me to where I can find information on it? Thanks, Mike K5ESS
| 12039
| 2015-12-18 19:43:47
| Dan Rae
| Re: PA3AKE Holy Grail RCVR
|
| 12040
| 2015-12-18 22:01:56
| farhanbox@gmail.c...
| Re: PA3AKE Holy Grail RCVR
|
| 12041
| 2015-12-19 05:08:31
| Steve Dick
| Re: PA3AKE Holy Grail RCVR
|
I believe you are referring to this high performance up-conversion receiver in the July/August 2013 issue of QEX magazine, called the HF7070. Quite an interesting read. There was also a follow-up articles: “A High Performance 45 MHz IF amplifier for an upconversion HF/LF Receiver” by Colin Horrabin, G3SBI, May/June 2015 QEX magazine “Some thoughts on developing high performance VHF oscillators” by Dr. Ulrich Rohde, N1UL” Nov/Dec 2015 QEX where he comments on the oscillator design in the HF7070. I am attempting to (slowly) build a version of the HF7070. My main problem is that I have a lack of test equipment to build it. I am building up a “Poor ham’s Scalar Network Analyzer” or PHSNA, a return loss bridge, crystal test fixture, attenuators, tw RF generators, combiner, etc. I will post when I have more info to post to the group. It will not have as good performance, as it will use lower performance components, but will still have very good performance. Some changes from the described design include: - RF front bandpass filters based on 4 pole butterworth filters using ELSIE and switched with Perigrine PE4250 switches. Optimized for ham bands but continuous coverage. Design done. - push pull Norton RF preamp from Clifton Labs driving a splitter – one path for the main receiver, another path for wideband SDR output spigot. - Switchable input attenuators - the 45-75MHz local oscillator based on an SI570 or some other single chip integrated device and a divide by 2 flip flop squarer - the second local oscillator based on a single chip fixed frequency device and a divide by 2 flip flop squarer - “Kiss” mixers based on the article by Chris Trask/N7ZYW “Mixer Musings and the KISS Mixer” - A pair of hybrid connected 4 pole 6 KHz 45MHz Vectron crystal filters from Vectron that I scored on EBAY that have very good specs. I will select two closely matched ones from a group of them - PHA1+ MMIC low noise high dynamic range preamp following the 45 MHz hybrid connected filters - Amplifier following the second mixer TBD - Digital downconversion and signal processing performed in a ST Microelectronics STM32F746G-DISCO for about $60.00. High performance floating point processor and large touch screen display built-in. - 8 watt low distortion STM class AB audio output chip used in car radios This is a challenging effort but I’m attempting it. Regards, “Digital Steve”, K1RF
| 12042
| 2015-12-19 05:59:56
| Lasse Moell
| Re: PA3AKE Holy Grail RCVR
|
Wow Steve!
You seem to undertake quite a projekt! Wish you good luck, and hopfully will bring this mammoth undertaking into harbour :)
Now PA3AKE, did shoot for a single conversion radio that aimed for the best. Period.
Please read all about it on this link:
It do have information on the 7070 up-conversion, but as you will see it is quite different.
One thing that is missing in PA3AKE-design is the finalized LO... he looked at various topologies, and found out some design flaws made by Analog Devices in their state-of-the-art DDS chip. Now I believe that newer chips has this corrected and my fit the bill. Using a Si570 may not give the perfomance you wanted...
Season Greetings
/Lasse SM5GLC
19 december 2015 14:08:26 +01:00, skrev Steve Dick sbdick@optonline.net [emrfd] :
I believe you are referring to this high performance up-conversion receiver in the July/August 2013 issue of QEX magazine, called the HF7070. Quite an interesting read. There was also a follow-up articles:
“A High Performance 45 MHz IF amplifier for an upconversion HF/LF Receiver” by Colin Horrabin, G3SBI, May/June 2015 QEX magazine
“Some thoughts on developing high performance VHF oscillators” by Dr. Ulrich Rohde, N1UL” Nov/Dec 2015 QEX where he comments on the oscillator design in the HF7070.
I am attempting to (slowly) build a version of the HF7070. My main problem is that I have a lack of test equipment to build it. I am building up a “Poor ham’s Scalar Network Analyzer” or PHSNA, a return loss bridge, crystal test fixture, attenuators, tw RF generators, combiner, etc. I will post when I have more info to post to the group. It will not have as good performance, as it will use lower performance components, but will still have very good performance.
Some changes from the described design include:
- RF front bandpass filters based on 4 pole butterworth filters using ELSIE and switched with Perigrine PE4250 switches. Optimized for ham bands but continuous coverage. Design done.
- push pull Norton RF preamp from Clifton Labs driving a splitter – one path for the main receiver, another path for wideband SDR output spigot.
- Switchable input attenuators
- the 45-75MHz local oscillator based on an SI570 or some other single chip integrated device and a divide by 2 flip flop squarer
- the second local oscillator based on a single chip fixed frequency device and a divide by 2 flip flop squarer
- “Kiss” mixers based on the article by Chris Trask/N7ZYW “Mixer Musings and the KISS Mixer”
- A pair of hybrid connected 4 pole 6 KHz 45MHz Vectron crystal filters from Vectron that I scored on EBAY that have very good specs. I will select two closely matched ones from a group of them
- PHA1+ MMIC low noise high dynamic range preamp following the 45 MHz hybrid connected filters
- Amplifier following the second mixer TBD
- Digital downconversion and signal processing performed in a ST Microelectronics STM32F746G-DISCO for about $60.00. High performance floating point processor and large touch screen display built-in.
- 8 watt low distorti
| 12043
| 2015-12-19 07:27:02
| Bill Carver
| Re: PA3AKE Holy Grail RCVR
|
I've built the front end. It works. Lots of work winding coils but the PCBs are superb. The DDS boards are a work of (engineering) art, superb layout. Getting the super-IMD 9 MHz xtals might be difficult unless there is another group buy from QT. W7AAZ
| 12044
| 2015-12-19 07:28:39
| Bill Carver
| Re: PA3AKE Holy Grail RCVR
|
Lasse, have you built Martein's AD9910/12 DDS board? Bill W7AAZ
| 12048
| 2015-12-19 11:48:35
| Lasse Moell
| Re: PA3AKE Holy Grail RCVR
|
Bill,
did not even know it exsisted! Thought he given up
| 12050
| 2015-12-19 12:16:35
| Bill Carver
| Re: PA3AKE Holy Grail RCVR
|
| 12052
| 2015-12-20 03:27:28
| Lasse Moell
| Re: PA3AKE Holy Grail RCVR
|
Bill,
guess I'm getting older. Once seeing these pages I do remember reading about it few years ago.. But it all slipped my mind. Very interesting and inspiring for sure. Wish I had a bit more spare time to do stuff like that. Guess I have to QRX for retirement, another ten years or so :)
Cheers and Season Greetings to everone on the list.
/Lasse SM5GLC
Is it not public, posted with his other receiver material??? Whew, thought I was losing my mind!
That text describes a DDS journey. Although for a dedicated traveller there is never a final destination. But sometimes you find the best place is not the latest. In that link you will find an AD9910 LO there and I believe that is the best today. Martein's AD9910 board is done right: analog and digital grounds are done properly, bypassing is correct, voltage regulation system is lower noise, and the output filtering geometry does not let things to leak around the filters. Martein found 1/f noise in the AD9910/12 design that compromises its phase noise performance. ADI corrected that in the AD9914 but the loss of two bits in the DAC increases the discrete spurious signals: they are shown in the data sheet. It seems to me the AD9910 is the best tradeoff for an HF LO at this time.
Bill W7AAZ
|
| 12068
| 2015-12-21 18:48:55
| lawrence_joy
| Re: PA3AKE Holy Grail RCVR
|
Lasse, What constitutes your partial kit? Do you have some or all of the PCBs? Crystals for the filters? Other components? Chassis? One thing the Holy Grail receiver lacks is a noise blanker, which I sent an e-mail to Martein about, and got an answer back several years back when I was still living in Singapore. The other receivers (transceivers) that have appeared in QEX and QST, like the one by Markus Hansen, VE7CA, and Cornell Drentea, KW7CD, have this circuitry. What would really be nice is the Gerber files for the PCBs plus PCB fabrication information.
73 de Larry |
| 12069
| 2015-12-21 18:49:10
| lawrence_joy
| Re: PA3AKE Holy Grail RCVR
|
Bill, Where did you get your PCBs?
73 de Larry |
| 12070
| 2015-12-21 18:49:36
| lawrence_joy
| Re: PA3AKE Holy Grail RCVR
|
Bill, Thanks for that tidbit of information about the AD9910 versus the AD9914. That is the kind of information I am on the hunt for.
73 de Larry |
| 12072
| 2015-12-21 21:24:19
| Bill Carver
| Re: PA3AKE Holy Grail RCVR
|
Martein has had group buys over the years. I bought the high intercept 9 MHz "QT" xtals and PC boards. He had some mechanical pieces to put subassemblies in, but I did that myself (I have fabrication tools for chassis/panels, etc). I don't know what the status is now. Bill
| 12073
| 2015-12-21 21:30:14
| Bill Carver
| Re: PA3AKE Holy Grail RCVR
|
All that info is from Martein, and Colin Horrabin, G3SBI. I watched as Martein found the sources of phase noise, the final one finding a noise generator inside the AD9910/AD9912 itself! Analog Devices removed them from AD9914 and it's quieter. But with two fewer bits it has worse discrete spurs. As Martein says, although the phase noise of the AD9910 could/should have been lower, they are still the best that's available. Bill
| 12075
| 2015-12-22 06:20:09
| Lasse Moell
| Re: PA3AKE Holy Grail RCVR
|
Larry,
I do have the PCB's for filter, mixer and IF... and did buy the inductors and caps from Italy. Oh yes do have tin boxes for the PCB. So no full kit... I do intend to start winding toroid coils any day :) Somehow life got inbetween and I have been quite busy with dayjob and such for the past year.
Cheers
Lasse SM5GLC
22 december 2015 02:06:32 +01:00, skrev lawrence_joy@yahoo.com [emrfd] :
Lasse,
What constitutes your partial kit? Do you have some or all of the PCBs? Crystals for the filters? Other components? Chassis? One thing the Holy Grail receiver lacks is a noise blanker, which I sent an e-mail to Martein about, and got an answer back several years back when I was still living in Singapore. The other receivers (transceivers) that have appeared in QEX and QST, like the one by Markus Hansen, VE7CA, and Cornell Drentea, KW7CD, have this circuitry. What would really be nice is the Gerber files for the PCBs plus PCB fabrication information.
73 de Larry
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