开云体育

But to use an SWR bridge one must power up the transmitter or provide another RF power source. With the readily available commercially built or kit form of antenna analyzers I feel that an analyzer is

Arv, Wrong group, No SSB or microphones, we are QCX this side :-[ some may use EFHW's though....... Alan

I use one of the Z-match tuner kits that have a tune/operate switch, with an internal bridge that protects the finals when tuning. Simply tune until the LED goes off or dim. ? There are several of

I have stated this before and will say it again. Get an antenna analyzer (I like the YouKits FG 01) and check your antenna or tune your antenna to the correct frequency first. Then hook it up to your

Lee W0VT Tune up with a BITX has always been problematic because there is no low power output mode suitable for use with restive SWR bridges.? I use an audio source that? can be adjusted for very

THEN, if no signal at either freq means neither the 328P nor the si5153 have an active oscillator. First thing I would suspect is power rails. Note that there is also a case where the 328 voltages

I would investigate building A resistive type SWR Bridge if they perform as "advertised"? http://www.gqrp.com/resistive_swr_bridge.pdf http://www.qrpkits.com/files/EZ_SWR20170527.pdf As always there

With just a length of insulatetd wire plugged into the receiver ant connector and then laid across the QCX board you should hear a good strong signal at both those frequencies. Just mate sure the wire

If one was going to use a random wire antenna matching the antenna to the QCX through the use of a tuner, how does one avoid hurting the finals until the tuner has a match?? I am assuming the radio

I don't have an oscilloscope, so I tried to listen on a general coverage receiver, but didn't find a noticeable tone at either 20 or 27 MHz. Skip, KG5SW

It's not obsolete, the MC3423 IC is still available in through hole & now surface mount :-) In the early days of 5v TTL logic IC's Designers used the "undesirable" feature that zener diodes posess to

Garry, IMHO this is a nice design. I built the ver 2. which was within a few mW of the measurement on my Racal power meter. I have just built a ver 3. unit though there is a s/w bug. Ron (Multus) has

Here is the meter I’m planning on building. I purchased the pre-built coils. https://www.multus-sdr.com/index.php?main_page=product_info&products_id=181 Garry / WD0DUD Sent: Monday, July 30, 2018

Yes, Crowbar. mixing metaphors. Thanks. t

Axe Handle? Google "over voltage crowbar circuits" The MC3423 IC was common in linear power supplies, it's probably being replaced by something bigger (smaller) and better Alan

I just fried my U3s with 12 supply. ?At a min I should have had it fused. Engineer friend noted that since this is a not uncommon problem for kit builders the U3s and other devices probably should

Hi, Tony The reason I asked you to try the code practice function is that I think you are barking up the wrong tree. There's no coon up there. All 5 of your "red box" voltages are connected with IC5

Indeed, the seconds indication on the clock takes 20 s to increase by one. What went wrong? Martin HB9AUR

/g/CalQRP/topic/another_no_kit_kit_from/23837923?p=,,,20,0,0,0::recentpostdate%2Fsticky,,,20,2,0,23837923 Roy WA0YMH [email protected]> wrote:

OOPS OOPS OOPS My bad. I had the columns switched. If you connected the QSX voltmeter to pin 3, and used a high impedance voltmeter to measure pins 1 and 2, you would find that all 3 were the same.