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Warning.? Danger Will Robinson. Doug, Be very careful.? Did you check the polarity of the input to the counter? I see you used the fancy connectors with polarized orientation. Every one remember

Ready for prime time. https://youtu.be/Yx9kqvf2S3c is the video of how I built and tested the Colpitts Crystal Oscillator using the PCB that I am labeling K7QO-001.2 as version 2 of the

I was lucky enough to get one of the beta boards from Chuck. I built it in about 20 minutes. It will get lots of use. Thanks Chuck for a great piece of test gear.

I have reworked Tony's Sprint Layout file and generated the proper gerber files and forwarded them on to Tony. Terry VK5TM

Lee, My interest was mostly the VXO tuning ranges. But I did measure some. For the same voltage range of 0 5 and 10 the BB910 measured, 52 22 8 pF comparable to the data sheet curve. This is

The links reference Tony's C: drive and we don't have access to that. I liked it as Project 3 but I no longer make pcb's so it's either Manhattan, ugly or gerbers ... Thanks Tony (in advance) for the

I have the following books left for sale with the prices I'm asking. All are in very good to excellent to like new. Some have my name in them. All have good bindings. The books that came with

Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the [email protected] group. *File:* k7qo-001.zip *Uploaded By:* chuck

Chuck, Do you plan on establishing a Wiki on this site. That's one of the Groups.io options. Mike K5ESS

Tony, gerber files aren't downloadable (or at least they won't for me). Terry VK5TM

What about using the body diode on a MOSFET? Because the body diode uses the substrate I guess it might have a large area and therefore capacitance?

So what were your reading for the BB910 ??? Lee, w0vt

Those were used to tune the bandwidth of the variable crystal filter. Used to provide RIT tuning/offset. Main tuning of the rig. You can use 1SV149 for all of the varicap diodes in the rig.?

Interestingly, a filter with narrower bandwidth can be made, but the terminating impedances are very low and the inserting loss goes up to unacceptable levels.? That's why I went with the 500 Hz

Used one of chuck/k7qo's diode-003 charts, to compare ranges. From 0 to 5 to 10 v the capacitance change is about: 1N4004 -- 14 7 5 pF MV209 -- 60 23 13 pF (about the same as the small

Howard - there's a PDF parts list and a CSV parts list in a K7QO folder entitled "Winter 2018 Project #1 -- NorCal40A qrp-tech PCB" I'm pretty new to groups.io, but let's see if I can include a

Karl, That's a good assumption. Gary Breed specified a 400kHz ceramic resonator but I tried other crystals and the noise generated was just as useful. I added a switch so I could choose various

Hello, I'm new to the NC40A builders party. It's official, 10 boards arrived by DHL this afternoon. The interval timer has officially started. I would like to organize my ordering of parts

Quit complaining. Two more stops and the rig will be half way to DXCC! It is amazing sometimes the circuitous route the various package services use. But, the above is one for the record

All of my spare boards are going in the mail today.. I hope the recipients will keep the group informed on their progress. They are K8IQY, WA4AR, W2JK, N2JJ, K5YU, KD5JGK, N2EAD and Russ VA? I