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Curt, Thanks for the info and your observation about selectivity. I am looking at the 38S schematic. It is an interesting design. 73, Alan, N8WQ

1.? It's the WARC bands.? Typo on my part. ??? I'll send back my UIL typing championship trophy. ??? Now you know why my postings are so long.? :-) 2.? I restricted the band search to the CW

If I did it, do I get to name it?? :-) I went to Aliexpress and ebay and looked up available crystal frequencies for off the shelf values.? I cheated and added one more frequency from the 1W values

Alan Some info here. Presuming industry may still have these crystals. https://www.qrp4u.de/docs/en/tables/index.htm Did my search on qrp vxo if combinations Note when IF must go up there is

Gang, Has anyone created a excel spreadsheet where one can experiment by either plugging in given crystal frequencies for the VXO and IF per Band or a table of popular crystal frequencies? Just

Ask and ye shall receive: <https://www.qsl.net/aa7fo/k7qo-crystal-parameters.pdf> The equations that I derived while a student were about 1962.? Eons ago. -- chuck adams, aa7fo QRP WAS 17m started

Found the following on the internet for those interested in such stuff for the SST project.? FYI and shown without any attempt at organization. The following shows quantitative results using two

Hi Chuck, Is there some way we can get a copy of your article? Thanks... Alan, N8WQ

Ian, What is your experience with using TL974 in the AF gain stage? When I tried those, the clicking sound from WiFi detection was very annoying. This seems to be a "feature" of the whole TL97x

Hi Mike The audio output has been divided into two channels of PWM.? One is for the high 6 bits and the other for the low 6 bits - it is a 12 bit value. This allows each PWM to be clocked at 64 times

Bill, Please excuse the intrusion; I don't wish to hijack the thread, but I have always found using a scope to be reasonably accurate from the bench. (I realize you may be wanting to do so in the

Ian, What a great project. Thanks for sharing! If you have 40-50db of opposite sideband rejection, I'd say you don't have any more work to do. That's excellent performance. I am curious about the way

Nick, Thanks for the heads up on that article. That, and EMRFD that was recommended, confirmed what I'd suspected: a basic diode detector, properly built and applied, can be a very accurate measure of

Hi Jerry Sorry for the late reply. I've been fixing bugs and investigating your question. I don't have an easy way of determining the side-band rejection, but on receive and listening to an S9 signal

Perhaps some one on the list has one excess to their needs.? ?My email address is Ki6ds1[@]gmail.com Remove the brackets to email. Thanks, Doug

I am new to HF / new to QRP / with a new BITX40 finally finished after sitting in the box forever Ron N7RDE

I like the BAV21, which is a high voltage, small signal diode. I built a wattmeter from an article by W8TEE and AC8GY in QST of November, 2018. It's an Arduino based project. I didn't build their

Ordered another set of 10 boards.? Here is what I get billed for. Subtotal: ? ? ? ? ?? $ 5.00 Shipping Cost: ? ? ? $ 6.34 Paypal Fee ? ? ? ? ? $ 1.17 Duty & Tax:vat help? $ 8.00 All

Mike, thanks for bringing that to our attention.? It solves a problem for the 40m SST.? It uses 4.000MHz x 4 crystals for the IF and BFOs and 11.046MHz for the VXO.? By using two 11.059MHz, which

This is an interesting paper on the NorCal site about VXO pulling, written by Wayne, NB6M. https://www.norcalqrp.org/nb6mvxo.htm [email protected]> wrote: