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Where to pick up +5V for envelope shaping for standalone 5W PA
I'm building the 5W PA for standalone operation, using the ATtiny84. Want to use the default 5ms shaping, for which the D pad should be connected to +5V. Just wondering where others have made this con
I'm building the 5W PA for standalone operation, using the ATtiny84. Want to use the default 5ms shaping, for which the D pad should be connected to +5V. Just wondering where others have made this con
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KI7MWA
· #63600
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Pin Confusion
#u3s
KM6WT: Okay, thanks. The purpose of the +5V-Heat pin jumper is to provide for the greater current flow needed by the TXCO oven. And, by the same token, if one is not using the TXCO, and one is using a
KM6WT: Okay, thanks. The purpose of the +5V-Heat pin jumper is to provide for the greater current flow needed by the TXCO oven. And, by the same token, if one is not using the TXCO, and one is using a
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KI7MWA
· #62553
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Pin Confusion
#u3s
N3MNT: Okay, but on page 3 of the synth assembly manual, the PCB tracks diagram shows that pins 8, 9, and 10 are connected together...and my DVM agrees. Pin 8 is not independent.
N3MNT: Okay, but on page 3 of the synth assembly manual, the PCB tracks diagram shows that pins 8, 9, and 10 are connected together...and my DVM agrees. Pin 8 is not independent.
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KI7MWA
· #62545
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Pin Confusion
#u3s
Another question: The diagram on page 15 shows +5V supply voltage applied to the PA pin, with the (upper) jumper connecting the PA pin to the +5V pin. But, with the (upper) jumper installed, the +5V s
Another question: The diagram on page 15 shows +5V supply voltage applied to the PA pin, with the (upper) jumper connecting the PA pin to the +5V pin. But, with the (upper) jumper installed, the +5V s
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KI7MWA
· #62544
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Pin Confusion
#u3s
N3MNT: "The lower jumper connects 5V to the heater if using the TCXO." So, in the case where one is NOT using the TXCO, the synth board makes a connection between the +5V pin and the Heat pin...just f
N3MNT: "The lower jumper connects 5V to the heater if using the TCXO." So, in the case where one is NOT using the TXCO, the synth board makes a connection between the +5V pin and the Heat pin...just f
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KI7MWA
· #62539
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Pin Confusion
#u3s
Page 15 of the U3S construction manual says: "To run the transmitter using the 5V supply, be sure to connect a wire between the +5V and PA pins. This is shown by the short red horizontal line in the d
Page 15 of the U3S construction manual says: "To run the transmitter using the 5V supply, be sure to connect a wire between the +5V and PA pins. This is shown by the short red horizontal line in the d
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KI7MWA
· #62532
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Si5351 Frequency Calculation
I've been playing with a 5351 breakout board & have a question about the way the frequency is calculated, and its limitations. Setting the PLL frequency is based on a crystal frequency (nominally 25 o
I've been playing with a 5351 breakout board & have a question about the way the frequency is calculated, and its limitations. Setting the PLL frequency is based on a crystal frequency (nominally 25 o
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KI7MWA
· #53961
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BPF 80m
Well...okay, I guess... Still, it would be interesting to learn how Hans was able to achieve an insertion loss of 1.27 dB (as reported in the bpf construction manual) while I have been unable to get l
Well...okay, I guess... Still, it would be interesting to learn how Hans was able to achieve an insertion loss of 1.27 dB (as reported in the bpf construction manual) while I have been unable to get l
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KI7MWA
· #53577
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BPF 80m
This discussion has been very informative, but has failed (as I see it) to respond to the original question, which is, what are the potential sources of insertion loss for the QRP-Labs standard bandpa
This discussion has been very informative, but has failed (as I see it) to respond to the original question, which is, what are the potential sources of insertion loss for the QRP-Labs standard bandpa
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KI7MWA
· #53557
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80 meter bpf toroid winding 30 turns givel 4.3 micro Henrys, not 3.8
I thank all for the advice. Clearly I've f***ed this up, so I've ordered another kit and I'm tossing this one.
I thank all for the advice. Clearly I've f***ed this up, so I've ordered another kit and I'm tossing this one.
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KI7MWA
· #52645
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80 meter bpf toroid winding 30 turns givel 4.3 micro Henrys, not 3.8
Here's my setup. The two cal standards lying over are the open and through. If you're familiar with QRP Labs products you will recognize the band pass filter, with the toroids unmounted. This is an 80
Here's my setup. The two cal standards lying over are the open and through. If you're familiar with QRP Labs products you will recognize the band pass filter, with the toroids unmounted. This is an 80
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KI7MWA
· #52623
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80 meter bpf toroid winding 30 turns givel 4.3 micro Henrys, not 3.8
So, I wound it again and got the design value (3.83 uH). The problem, really, is that, tuning with the nanovna, I have to reduce the turns to 28 (I've done this 3 times now), and when I trim the extra
So, I wound it again and got the design value (3.83 uH). The problem, really, is that, tuning with the nanovna, I have to reduce the turns to 28 (I've done this 3 times now), and when I trim the extra
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KI7MWA
· #52616
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80 meter bpf toroid winding 30 turns givel 4.3 micro Henrys, not 3.8
Been assembling an 80 meter band pass filter, and have consistently had to remove 6 turns during the tuning phase (using a nanovna). This most recent attempt, I used my Peak LCR45 to measure the initi
Been assembling an 80 meter band pass filter, and have consistently had to remove 6 turns during the tuning phase (using a nanovna). This most recent attempt, I used my Peak LCR45 to measure the initi
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KI7MWA
· #52615
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Deliveries for QCX+
Do not forget the various unexpected delays. My most recent order spent several weeks in US Customs because (apparently) there was some packaging mishap. Then, without further notification, it appeare
Do not forget the various unexpected delays. My most recent order spent several weeks in US Customs because (apparently) there was some packaging mishap. Then, without further notification, it appeare
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KI7MWA
· #50470
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Formal customs clearance required
Finally some news: Packaging damaged. Repacked and forwarded for delivery Must be my bad shipping karma again.
Finally some news: Packaging damaged. Repacked and forwarded for delivery Must be my bad shipping karma again.
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KI7MWA
· #50197
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Formal customs clearance required
My most recent shipment was reported as "Formal customs clearance required" on July 07. No further updates since then. Anyone else have similar experience?
My most recent shipment was reported as "Formal customs clearance required" on July 07. No further updates since then. Anyone else have similar experience?
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KI7MWA
· #50193
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Kit shipping
Hans' control ends when he drops your shipment off at the local collection point. My U3S case arrived more than a week before the kit. My most recent purchase has been languishing in US customs for 5
Hans' control ends when he drops your shipment off at the local collection point. My U3S case arrived more than a week before the kit. My most recent purchase has been languishing in US customs for 5
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KI7MWA
· #49959
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What conduit can do it - way OT
I suppose I should also mention that the route will be taking the feed line past things like a 120VAC to 12VDC transformer.
I suppose I should also mention that the route will be taking the feed line past things like a 120VAC to 12VDC transformer.
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KI7MWA
· #49872
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What conduit can do it - way OT
It is more the "pushing on a noodle" problem. I need enough rigidity to shove it through the places I can't reach, but not so much I can't work it around obstructions. And, there is a problem with the
It is more the "pushing on a noodle" problem. I need enough rigidity to shove it through the places I can't reach, but not so much I can't work it around obstructions. And, there is a problem with the
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KI7MWA
· #49869
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What conduit can do it - way OT
This question comes from out in Left Field...but I couldn't think of a better place to start an inquiry... I need to run my coax feed line through a mess of plumbing/wiring/metal studs/etc. There is n
This question comes from out in Left Field...but I couldn't think of a better place to start an inquiry... I need to run my coax feed line through a mess of plumbing/wiring/metal studs/etc. There is n
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KI7MWA
· #49867
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