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Re: Stacking cores for T1
If one uses #30 AWG wire, I don't find the number of windings to be troublesome for the 60 metre version, other than the counting of the turns - lol
Stacking two cores on 80 metres would certainly be a valid method of reducing # of turns. I had mused that if I were to ever build a 30m or 20m version, I would use a T50-7 core, as it has nearly the same AL as a T50-2 but less loss and better stability (and I have a bag for 25 in my parts stash)... vy 72 de va3rr |
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Re: Stacking cores for T1
On Tue, 2017-11-14 at 12:23 +0000, Chris Wilson wrote:
Hello G0DZB,See "How are properties affected when cores are stacked? Stacking core will increase the cross section (Ae) by the multiple of the number of cores in the stack. The magnetic path length (le) will remain constant. The AL can be estimated by the same method as for single sets, where a leakage adjustment is estimated based on the ratio of window area (WA) to core area (Ae). Because that ratio decreases as cores are stacked, the AL of n stacked sets is slightly less than n times the AL of a single set. " PeterO G0DZB |
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Re: Stacking cores for T1
Hello G0DZB,
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Sticking my ignorant neck out here, but WOULD stacking them reduce the number of turns needed? I would have THOUGHT it would just raise the point at which a transformer wound upon them saturated the cores? Tuesday, November 14, 2017 Has anyone tried stacking two T50-2s for T1 on the lower frequencies to PeterO -- 2E0ILY Best regards, Chris mailto:chris@... --
Best regards, Chris Wilson (2E0ILY) |
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Re: L C Meter
Alan, Thanks for the reply. Sorry, my marble example mixed (apples and oranges) GDOs and LC meters. I just muddied the water with that example. Also, I stand corrected, yes, a standard reference? component is required to measure reactance using a GDO and balanced bridge. Ken, Thanks for the reply. In your example... where A + B = 1376 and A = 939 then by arithmetic (component under test) B = 437 In this case 'A' is the 'uncalabrated' 'standard' as such it's absolute value is not an issue. ? Parallel in a third capacitor defined C, now for example... (A + C) + B = 1876 then remove B now 1439 is indicated on the meter.?? Therefore? 1876 - 1439 = B = 437 With respect to your friends meter and difference in measured values of same components. Capacitance measurements are frequency dependant. I assume your LC meters were on different frequencies. ...... I will take this topic off line until I better understand probably error at higher frequencies and very small capacitor values..... 72, 73 John N3AAZ |
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Re: WSPR result by QCX
Hi Bob, Hidehiko=san Congratulations, both of you! This must be the first known QCX - QCX contact! Although it is on WSPR (Hidehiko-san's QCX transmitting, Bob's QCX receiving).? If anyone works QCX - QCX on CW please let us all know! 73 Hans G0UPL On Tue, Nov 14, 2017 at 1:37 AM, Bob Sutton via Groups.Io <zl1rs@...> wrote:
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Re: U3S transmitting- how to troubleshoot
Hi Ryan The instructions for Rev 5 are on the relay kit page? - and even the instructions for Rev 1, 2, 3 and 4 can also be downloaded from there.? The jumpers look fine.? The highest frequency you are going to use, should be in slot 1.? 73 Hans G0UPL On Tue, Nov 14, 2017 at 3:59 AM, Ted Timmons <ted@...> wrote:
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Re: QLG1 Gps Receiver module
IC2 has 5vdc on pin 3 and no voltage on pin 1 & 2, also extremely hot.John, A hot regulator with no output usually means that the output is shorted to ground. Check C24 is the correct way round. Check for solder across tracks. 73 Alan G4ZFQ |
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Re: Prog Rock Voltage test
¿ªÔÆÌåÓýG'day Justin. You are a little ahead of me in this Prog-Rockery but I see it this way:- The 317 is the first regulator from 10.5 to 5.25. It could be trimmed down. The 2nd regulator is the Q1 Q2 Q3 group aiming at a quiet 3.3 to 3.5V Therefore you need to check every little detail in that area for values and continuity and orientation. If that fails you might check for rogue oscillations with a CRO or sweeping across with a radio RX on the MW and SW bands as there should be no other oscillators at work with IC1 and Synth unplugged. I have seen no mention of that sub-cct being unstable at all in the I/O group. Best of luck - 73, John, VK6JY ________________________ On 14/11/2017 9:02 AM,
freefuel@... wrote:
voltage check on my ProgRock I'm running 10.5 volts into the LM317, and I'm getting 5.25 Volts on the 5 volt pin, on the 3.3 volts pin I'm measuring 5.74 volts with my Fluke 87 multi meter.? What could cause the 3.3 volt rail to read higher then the regulator output? |
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QLG1 Gps Receiver module
I am having problems with my GPS QLG1 module. When connected I have the red and yellow LED on solid. Never see the green. IC2 has 5vdc on pin 3 and no voltage on pin 1 & 2, also extremely hot. Should I assume a bad LM317LZ or could there be another problem that would cause it not to output the 3.3vdc? If it is a bad voltage regulator is the part available |
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QLG1 Gps Receiver module
¿ªÔÆÌåÓýI am having problems with my GPS QLG1 module. When connected I have the red and yellow LED on solid. Never see the green. IC2 has 5vdc on pin 3 and no voltage on pin 1 & 2, also extremely hot. Should I assume a bad LM317LZ or could there be another problem? If it is a bad voltage regulator is the part available Thanks for any info, John? KF4HRY ? |
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Re: Prog Rock Voltage test
voltage check on my ProgRock I'm running 10.5 volts into the LM317, and I'm getting 5.25 Volts on the 5 volt pin, on the 3.3 volts pin I'm measuring 5.74 volts with my Fluke 87 multi meter.? What could cause the 3.3 volt rail to read higher then the regulator output?
-Justin N2TOH |
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Re: U3S transmitting- how to troubleshoot
Ted Timmons
Thanks Ryan. I'm working from the LPF relay board down to the main board.?Can you look at my relay jumpers, especially at the 1 and 5 ends? It's the rev5 board, which (I think) is different than the rev4 instructions, I think I'm missing a jumper on the 1, but I'm not sure which pins should be jumped since the layout is a little different. smaller pic:? I looked through two assembly manuals and the operating manuals, I don't see it again, but I swear the relay ordering was important. Can someone point me at that? On Sat, Nov 11, 2017 at 10:42 PM Ryan Flowers <geocrasher@...> wrote: Follow the RF path from the BS170 Q1 to the RF output with a continuity tester. It won't pass the capacitor, so just test the path both sides of the capacitor. If the path is good, then make sure you check the bias of Q1. I measured idle current and just tweaked bias until it was about 5ma higher than idle, and left it, and I'm getting about 350mw out. Plenty good!? |
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Re: Power output on 20 meters.
"When I wound all the toroids and TI, I scraped all of the enamel off of lead wires with a sharp hobby knife (Xacto knife) right up to the core, and then tinned them.? I wanted to be sure, that I would have a good electrical connection when I soldered them to the board."
I wonder if this is an "all or nothing" as I had hitherto thought, i.e. you either have 100% contact or 0%. I'm beginning to think that the way you did that, may be important to getting the maximum out. It'd be interesting to see, with your already quite good results, if you reach the spec by checking the inductance of each L1 to L3 and removing turns if necessary. BUT do not mess up a good thing you are happy with on my account!!! Your results sound very good as they are! |
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QCX transceivers used as QRSS Grabber Receives
¿ªÔÆÌåÓýDear Members, ? I have just had my third day using the 30M QCX transceiver as the receiver for my 30M grabber.? It is doing an outstanding job.?? It has a Nice 200Hz bandpass in the stock radio kit that I don¡¯t think needs to be modified to work as a grabber receiver.? At the present time I Have it married up to a PC running Spectrum Lab but want to also try it with a LOPORA Raspberry Pi spectrum Analyzer. ??It has very good sensitivity and appears to be stable in frequency.? Here is one of my spectrum Analyzer Pictures: ? The stations KC5EVR and KJ6ANV are local stations.?? ZL4EI is a real long ways away.? ?I am located in Las Cruces, New Mexico. But this the presentation I am Getting using a QCX receiver with no modifications.? I just built it and plugged it in and turned it on after doing the Adjustments.? ? Take care and have fun.?? QRSS is a BLAST, even at mW¡¯s 73 Dave Hassall WA5DJJ? Las Cruces, New Mexico Website: http://www.zianet.com/dhassall/ ? |
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QCX 40 problem
George H. Gates
Turned pwr on. Did alignment. Rcvr working great. Decided to set cw speed befor transmitting. Set speed to 16wpm. Now cant get out of that menue. Turn pwr off. Now nothing shows on display. Display blocks are lit up and I see bright line flashing and moves up the display. still no words. help ?George/W2BPI
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va3rr
Enno Korma, PF5X
Hidehiko Komachi - JA9MAT
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