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Re: K1 For Sale
Dale Holloway, K4EQ
Forgot to add that the K1 is a 4-bander: 40, 30, 20, 17 meters.
-- Dale Holloway, K4EQ www.k4eq.net
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K1 For Sale
Dale Holloway, K4EQ
I just bought an Elecraft KX2 (I'm awed!) and have decided to put my beloved K1 (SN 3161) up for sale. It has the noise blanker, automatic antenna tuner, internal battery adapter, and tilt stand. Also included is the K1BKLT LCD back light modification kit, which I never installed. I built this in September 2012 and it is in impeccable condition cosmetically and operationally. $395 plus shipping via PayPal. Go to www.k4eq.net and click on "For Sale" for pictures. Email information is also available on the site.
-- Dale Holloway, K4EQ www.k4eq.net
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Re: KiCad Tutorial
WØIY <barry.w0iy@...>
Look for the DigiKey videos. Shawn does a good job on those. If the date of the video is more than a year old, it may not be accurate. The biggest change from V4 to V5 (5.1 is the latest release) is in the Libraries all moved to a different file location and names. If you have never installed V4, then a new clean install of V5 should just work with the Libs in the correct place.
Most other topics should be similar from V4 to V5. Rumor has it there was a perfect CAD tool, but it died a long time ago in a galaxy far far away when the Empire destroyed its planet. A single SD card may have survived. (8-)
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Re: MOSFET PA RF Choke?
nm0s_qrp <ai9e_qrp@...>
It is difficult to speak intelligently on this design without seeing a schematic, but it is not at all unusual to have a low-inductance choke between the drain of the PA MOSFET and the supply, _if_ it is resonated against a parallel capacitor at the operating frequency to create a high impedance at the drain. This capacitance may exist in parallel to the drain-source of the MOSFET, and have a return through a larger RF decoupling capacitor in parallel with the supply voltage. The low value choke may let RF current pass, but as long as it is a high Q circuit, there is no RF power being dissipated.
73 Dave NM0S
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Re: MOSFET PA RF Choke?
nm0s_qrp <ai9e_qrp@...>
Whose design is this? Is there documentation anywhere that others could see?
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Re: Magic box build, no sidetone
On 4/22/2019 5:03 AM, Jim Kortge wrote:
Sorry, 2N3904 transistors at Q14 and Q15; hands don't seem to be working at 5 AM this morning. Replaced R46 from 10meg to 100 ohm.That change has nothing to do with the side tone generation.Prior tests ok.What were your voltage readings in those tests?Is this a known problem?No, not at all.Suggestions?Send photos and answer questions and I'll try to help you.
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Re: Magic box build, no sidetone
On 4/21/2019 4:28 PM, Kenneth Ketner via Groups.Io wrote:
Greetings folks.Hello Ken, Finally getting around to building Magic Box.That kit is getting long in the tooth! :-) Can’t get a side tone at the side tone test step.Can you send along a photo of the PCB as it currently is built, top and bottom sides so I can have a look at what you've done so far? Can you verify that there are 2N3804 transistors at locations Q14 and Q15 and a 2N7000 at location Q16? Replaced R46 from 10meg to 100 ohm.That change has nothing to do with the side tone generation. Prior tests ok.What were your voltage readings in those tests? Is this a known problem?No, not at all. Suggestions?Send photos and answer questions and I'll try to help you.
72/73, Jim, K8IQY - The MagicBox Designer
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Re: MOSFET PA RF Choke?
Leland L. Bahr
Yes, I agree with everything you said. I also don't understand
how 25 ohms could choke out RF from feeding back into the power
supply. Lee
On 4/21/2019 5:20 PM, Curt via
Groups.Io wrote:
Studying a 5 watt 40M Transmitter that uses an IRF510 for PA, what is puzzling is the RF choke is specified as a T68-2 with 10 turns. By my calculations this presents an impedance at 7 MHz of about 20 ohms, which seems way less than the 30 times output impedance rule. Am familiar with 10 turns on an FT37-43 which presents an impedance of about 1500 ohms, have encountered other IRF510 PAs that used that type choke. How can the low impedance choke keep RF from leaking out of the output circuit to the power supply?
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MOSFET PA RF Choke?
Curt
Studying a 5 watt 40M Transmitter that uses an IRF510 for PA, what is puzzling is the RF choke is specified as a T68-2 with 10 turns. By my calculations this presents an impedance at 7 MHz of about 20 ohms, which seems way less than the 30 times output impedance rule. Am familiar with 10 turns on an FT37-43 which presents an impedance of about 1500 ohms, have encountered other IRF510 PAs that used that type choke. How can the low impedance choke keep RF from leaking out of the output circuit to the power supply?
The same circuit uses a 2N3053 as a driver, the collector being coupled to the PA via a transformer that uses an FT37-43 with 14 turn primary ( 3000 ohms @ 7 MHz ) and a 4 turn secondary ( 246 ohms ). I am suspecting that the core types have been transposed. If so, then the choke would be 1500 ohms and the transformer would be 49 ohm primary with a 4 ohm secondary. These seem more what should expect? Comments? Curt KB5JO
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Magic box build, no sidetone
Kenneth Ketner
Greetings folks. Finally getting around to building Magic Box. Can’t get a side tone at the side tone test step. Replaced R46 from 10meg to 100 ohm. Prior tests ok. Is this a known problem? Suggestions?
73, Ken Ketner ka5eld
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DMR & QRP nets
Paul AI4EE
Well, it looks like it will be a while before I can check in to the talk
group. The only DMR repeater I can reach is on a TV tower, and the TV people are upgrading everything. No internet for maybe months yet. I'm not willing to shell out $$$ for a hotspot, the rig was enough. I will be getting some wire in the air soon, so maybe I can hit the 40 or 80 nets on Wed. Paul, AI4EE near Raleigh, NC
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Bayou Jumper For Sale
cpa599@...
$80 shipped.
Built - 1 xtal. Needs minor, minor fix (no power). With Hobby Lobby box. Pics on request. W8EJO
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Re: KiCad Tutorial
Michael N6MST
Keep in mind the Contextual Electronics tutorials are not using the latest version of KiCad, I ran into some trouble using KiCad 5 with those videos, got frustrated, haven't gotten the motivation to go back!
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Re: KiCad Tutorial
Oh, yes, Chris! He and Dave Jones down under do the Amp Hour podcast. They're great!
On Thu, Apr 18, 2019 at 3:12 PM davemrtn <davemrtn@...> wrote:
--
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Re: KiCad Tutorial
davemrtn
Never mind, I finally stumbled onto it.... Contextual Electronics at... https://www.youtube.com/watch?v=PlDOnSHkX2c David Martin - NA1MH - Mountain
Home, Ar.
----------------------------------------- Wherever I go, there He is. Recycle, Reuse, Re-purpose, Repair >Professional Sports - An activity for small minds< !! There is a reason it is called "Sports Trivia" !!
On 4/18/2019 14:08, davemrtn wrote:
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Re: KiCad Tutorial
John Evans
Not on youtube and not free but cheap. I highly recommend this course and instructor. Sales go on periodically and right now it is dirt cheap. https://www.udemy.com/kicad-like-a-pro-2e/
On Thu, Apr 18, 2019 at 1:08 PM davemrtn <davemrtn@...> wrote:
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KiCad Tutorial
davemrtn
Who is it that has good KiCad
Tutorials on youtube ? -- David Martin - NA1MH - Mountain Home, Ar. ----------------------------------------- Wherever I go, there He is. Recycle, Reuse, Re-purpose, Repair >Professional Sports - An activity for small minds< !! There is a reason it is called "Sports Trivia" !!
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40m Net
dekle <dekle@...>
Storms in the area so a lot of QRN but still got a couple:
WA9PWP Paul WI (on his HB1B) AH6AX LARRY MD WA9PWP Paul WI (this time on his shiny new Hilltopper 40 - which sounded great !) C U next time 73 Bill KV6Z
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80 meter Net
Ge Group I have Thunderstorms nearby by, so I have pulled the plug. Get on call cq see who is out there. Cu all next week 72 Johnny AC -- Check out the 4SQRP website at 4sqrp.com
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Wednesday Evening 40 and 80 meter Nets - Wed, 04/17/2019
#cal-notice
main@4SQRP.groups.io Calendar <noreply@...>
Wednesday Evening 40 and 80 meter Nets When: Where: Organizer: Description:
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