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I actually did this mod twice. First with the .1mf caps. I did this on my 40m version and when I removed the old cap and put in the new I did not have ANY audio. After investigating I found that I

I'd have to disagree, I'd say an SWR meter is more difficult to build, Stockton uses toroids, prepped coax and needs some care taken with how you stuff it into the box or you get 'cross talk' but as

Tony That now shows IC8/9 are as expected. In similar RXs I've known C45, 46 voltages to vary according to tuned frequency. This will make IC5-5 differ. IC6-3 probably depends on the position of R24.

What results did you see when you listened for the two oscillators (20 mhz & 27 mhz)? -- Wes AE6ZM Sierra Vista, AZ

Ahem. Sorry. Here it is.

Tony, I do not see it. 73 Alan G4ZFQ

Hi Alan, Erik Agreed... though everything is a compromise. Ability to manage 200 users simultaneously, across all of HF is impressive indeed. However your quoted difference between a strong and weak

Erik, I said "Taken to the extreme" Your figures do not give other vital parameters. Yes, it is a good receiver but I'm suggesting that it would be even better for a particular frequency of interest

Jim, Why do you say that? The readings on the chart in the QRP Labs manual are made with the low impedance internal meter. Tony, using a high impedance DVM said "The voltages around IC8 and IC9 are

I have measured the voltages with the internal meter to be more consistent with the data. There are some glaring differences! Here is my new, revised chart. I have highlighted differences over 10%. I

If you just care about power measurement, not SWR, The QRPlabs dummy load is excellent. I own one, and it has very good measured return loss over the HF bands. Notably, it has a built-in diode

Hi Hans, Your contributions particularly those requiring the use of a soldering Iron are always appreciated. :-) Alan

Hi Clint, (I have being proved wrong before....) My thinking is SWR meter are easier to build? Specifically we are interested in a RATIO of FWD / REV power, rather than absolute values of power to

Hi, Tony If the voltmeter has a high enough input impedance that it didn't load down pins 3 and 5, then IC8 is hosed. Replace it with any reasonably decent dual op amp - TL072, TL082, 4558, etc.

Wow, many thanks for all of your responses,?I will certainly look into all of these suggestions. Actually I ordered the The QRPlabs dummy load along with my QCX40, so I could certainly build

The University of Twente WEbSDR is a nice example of what a wide bandwith ADC (16 bit, 80Msps) based receiver could deliver. It receives continuous 5kHz-29000kHz with receiver noise below -110dBm,

Power is 'easy', dummy load, a suitable diode and a capacitor rated for the voltage, there are a few projects on the 'web for that complete with the calculations you need to work out power from

All: There's an article coming out in the Nov issue of QST that has a combination dummy load and watt meter that costs about $20 to build. It uses the venerable quart of mineral oil, but can easily

Hi Alan Hi hi. I don't know about being famous. Being very busy, for sure... I used to be a contributor when I had done something that seemed interesting and other people might like to know about. I

Ted, QCX = $50 You don't need to spend $150 on a power meter if you don't want to. You said that home brew appeals. If you have not already, see if membership of the GQRP Club has anything to offer?