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Re: d4d off frequency
i used my k2 to measure it.
By ron mcmurray · #2813 ·
New Facebook Group for D4D
Folks, You are invited to join the new group. https://www.facebook.com/groups/487925331780070/ Thanks, Adam
By Adam Rong · #2812 ·
Re: d4d off frequency
Ron, If you measure by a frequency counter or other devices with a probe, the capacitance introduced by the probe will pull low the oscillator frequency, and 2kHz is a reasonable number. You can
By Adam Rong · #2811 ·
d4d off frequency
my d4d is off frequency, low by 2khz . do i decrease or increase capitance. it's at 14.272. thanks, ron kc0tdj
By ron mcmurray · #2810 ·
Re: D4D mods
In my test, I used 1N4148 but any diode will do, like 1N914, 1N4001-4007, 1N5817 and etc. [email protected]> wrote: -- Thanks, Adam Rong
By Adam Rong · #2809 ·
Re: D4D mods
What diode is recommended for Steve's Mod?
By Simon C <symen79@...> · #2808 ·
Re: dB level and TX timings
Hi Conor EI6GSB, Thanks for reporting this. I have never met this before. If you have spare part, you can try to swap NE602 to see if it is better. Also, check if you have properly attach the final
By Adam Rong · #2807 ·
Re: dB level and TX timings
Hi all again, After some more investigation I believe this simply may be a case of the transceiver overheating. I opened the case to inspect the board to see if there were any signs of component
By Conor Farrell · #2806 ·
Re: D4D mods
Modification is not necessary if you want to get it work first. After you have time, you can consider these two modifications: 1. Replace C5 by a 105 monolithic cap (tolerance < 20%) to improve IMD
By Adam Rong · #2805 ·
Re: D4D mods
I just received my d4d kit this week, and wish to incorporate all recommended mods. Will there be a file that lists all mods, or an update to the instructions that includes all? *Bryan B. Brauer,
By Bryan Brauer · #2804 ·
Re: D4D mods
Steve, Thanks for reminding. We studied the spec while we apply the 4.3V power supply. The main impact parameters are: Conversion gain, Noise figure, and IP3i I believe the major impact is IP3i
By Adam Rong · #2803 ·
Re: D4D mods
I would remove the diode in series with the 5V to the SA602. The minimum operating voltage for the SA602 is 4.5V and performance degrades quickly below 4.5V. Thank you, Steve. Your diode mod is
By Steven Weber <steve.kd1jv@...> · #2802 ·
Re: D4D mods
And the photo follows. The left side is the KD1JV diode mod, and the right side is the BH4DCL diode mod. [image: ΢ÐÅͼƬ_20190804230531.jpg] [email protected]> wrote:
By Adam Rong · #2801 ·
Re: D4D mods
Thank you, Steve. Your diode mod is effective. In my test, the carrier leakage improved by about 5 dB, as a side effect, both USB and LSB signals increased about 1 dB which is a surprise to me. I also
By Adam Rong · #2800 ·
dB level and TX timings
Hi all, I built the D4D kit a couple of days ago and it worked well. I didn't make any QSOs just yet, but the band conditions are not good so this isn't a problem. Yesterday, however, I powered up
By Conor Farrell · #2799 ·
Japan Ham Fair 2019
Folks, I have decided to join Japan Ham Fair 2019 this year. It will be a fast in fast out trip but I should be able to stay at QRP village booth for about 1 day from August 31 noon to September 1
By Adam Rong · #2798 ·
Vacation August 6-11
Folks, I will be on vacation from August 6 to 11. I will reserve something at my shipping agent, but likely will not be able to cover all your need. The next shipping will be August 19. I still take
By Adam Rong · #2797 ·
Re: Great Kit
Many thanks for your information. good luck yves
By yves delaforge · #2796 ·
Re: Great Kit
samir, Nice job on the building and QSO made. You are welcome to join the contest this quarter. Thanks, Adam
By Adam Rong · #2795 ·
Re: Great Kit
just a heads up the oven resistor needs to touch the crystal case.
By N8DAH <Dherron@...> · #2794 ·