开云体育

Ok you could do what I did and use a band switch. You can order a multi poll bandswitch and do it manually for the bandpass filtering and use external low pass filter for say 80 and 160m. Sent from

Henning and all, I am not sure the individual-chokes-method is a mistake: my understanding is that technique results in a substantial improvement in IMD. Remember, every design decision is a

: I have two Raduinos here, one that came with my uBitx and is working 100% with supplied firmware the other is one that was for my Bitx40 that I modified to use with the uBitx. I loaded it with the

Hi Since you're interested in AM radios that glow in the dark, have you looked at the Pine Board Project 75m AM radio?? You can get more details

All, I guess that there are two design mistakes: 1. the supply voltage to the drains of the transistors is fed via individual chokes, not the "balancing" dual winding choke 2. the input cpacitance

Added a 1-transistor amplifier (12volt wall wart supply) to increase my square wave input to the bridge swr measurement. Aimed for couple of volts rms. 2n3904, schematic to follow. Turns out

This is what is recommended. https://www.cmlsupply.com/kester-ep256-lead-solder-paste-63-37-syringe-dispenser/

Placing down the solder mask has been a big problem for me. My stuff (Mechanics Brand - Lo Tempt) from eBay is in a small jar.? I keep it in the refrig, it nasty stringy. I have tried a sewing

That blinky light board looks good as a first intro. Let them know it is possible to find kits with just 1206's and SOIC's like the 555. Use a good hot fine tipped soldering iron and appropriately

Mornin' Ken: You're right, and I may have glossed over this idea too quickly. This might be a great way to get them to try at low expense and without insulting their fabrication abilities. I do have

Band (filter) switching would require some IO pins to drive relays. Unfortunately there's only one free IO pin left: pin A2 (previously used for calibration). With just one IO pin we could only switch

Hi, I tried the uBITX with FT-8 on 20m, and I could easily hit 5W out and probably higher.? I've observed that typical SSB usage doesn't come close to CW output power, but the signals coming out of

The simple way to do this is to do what Hans did on the 5W PA he produces at QRP-Labs…. There is a second set of pads on the PCB that has the right pinout for the RDxx devices. That way you can

This may be a futile attempt if the intermediate gain stages (pre-driver and drivers) fall off with frequency too. I have not done this myself yet… still on my list… to actually publish a table

I'm using V2.03 on my bitx40 with great results. With all the nice features, I was thinking about adding an extra band or two or even more to the rig.? Would it be feasible to add multi band options

I ordered mine 31dec mine will come with the easter bunny hopefully with more up to date software been as the first run was betas chris

Thanks all. I'm not looking to stun pigeons, but it would be nice to have 5 watts on 30, 20 and higher if the solar activity ever picks up. There is also a RD16HVF1 discussion in the "irf520 vs

I ordered my 2nd one on 23 December, 2017 and I received information from HF Signals that it would be in about 2 weeks before it shipped and they apologized for the delay. As fast as the pre-orders

Hello Jack, W8TEE, The SMD components are not the only thing that you might need. Also look into: Solder paste in a syringe with application needles (~ $20+ for 35gm) Toaster Oven or Electric Skillet

Allard Thanks 73 Dave G8PGO