History of Changes


The Marh-2011 groupbuy effort has finally come to an end now. I am completely sold out! Anyone interested in a new groupbuy feel free to send me an email and I will keep you informed.

The main groupbuy info page has been updated and pictures of the various PCB's and other items that have been distributed sofar are added. See: Groupbuy Info


This is a major update involving the 5 new boards designed from scratch over the last 2 years. A high performance back-end has been added to complement the frontend into a complete finished receiver signal path from antenna to speakers. DDS local oscillators and Controller + Software will be added next to finalize the receiver.

See: Down Conversion Receiver


Measurement data of the AR7070 2nd prototype has become available.

Have a look at: AR7070 Prototype2 Measurements


Colin Horrabin, G3SBI, has an update on the developments around the new AOR7070 shortwave receiver.

Have a look at: AR7070 Progress Updates


Colin Horrabin, G3SBI, has an update on the progress made with the development of the new AOR7070 shortwave receiver.

Have a look at: AR7070 Progress Updates


The group-buy October-2008 has finally closed! However I have one PCB-set left. It is incomplete though. It is missing the frontend board. This would not be a problem for anyone just wishing the build the BPF assembly as a preselector for an SDR for instance. Also the frontend board can be home etched fairly easily with the layouts available on this website. Just send me an email if interested!

The october 2008 frontend groupbuy


This is an update to report on the evaluation of the AD9910 DDS chip to be used as the DDS-Local Oscillator that complements the Down Conversion Frontend. The research regarding the AD9910 and especially its noise characteristics is finished. However, details on the final construction and integration with the down-conversion frontend are the subject of a future update!


A favorite links page is added!


I am currently working on a local oscillator (LO) that should performance wise match the Down Conversion Frontend presented on this web-site. The main issue here is low phase noise. Given the frontends best intercept point being slightly over +50dBm, the noise sidebands of the local oscillator must be down to at least -153dBc/Hz only a few KHz off carrier in order to have the receivers noise floor, raised by reciprocal mixing, be less than IMD products in the presence of very strong out of band signals. This is quite a design challenge that cannot be met with even the best PLL based synthesizers.

The new Analog Devices AD9910 DDS chip is a good candidate for an HF LO with extremely good phase noise performance according to its datasheet. However at this point the measured noise sidebands of the AD9910 do not reach the superb low levels claimed by Analog Devices. It does not even come close. I am using 2 different techniques to measure noise that both yield the same results. At this moment I am working on a 3rd measurement method in order to confirm the other 2!


Colin Horrabin, G3SBI, has an update on the progress made with the development of the new AOR shortwave receiver.

Have a look at: AR7070 Progress Updates


The october 2008 frontend groupbuy


The august 2008 frontend groupbuy


Minor update: Added part lists to the BPF box documentation PDF's.


Release of the frontend board with additional 500Hz CW roofing filter. This update is complete with schematics, part list, PCB artwork and last but not least extensive performance measurements.


Release of the final 10 band BPF filter box with associated measurements and PCB artwork.


Update with G3SBI's report on his high dynamic range 45MHz IF up-conversion frontend using the FSA3157 H-Mode mixer.


Update regarding RZ4HK's innovative TLT-Mode mixer.


Update regarding a 120dB IMD3DR down conversion frontend with FSA3157 mixer, 9MHz QT quartz roofing filter and a 40M band pass filter.


Initial web release focused primarily on the H-Mode mixer.

Many smaller updates followed, of which I have lost track, when more bus-switches and transformers were put to the test. One of those was I7SWX's 2 transformer version!

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