开云体育

I am going to bend up a case from Brass sheet and I plan to use the case for the heat sink. I will have to use insulators to electrically isolate the finals. It should give me a much bigger surface

I have a receiver here with a first IF of 45 MHz and coverage very slightly more than the ubitx. It has eight filters and very few (maybe none) birdies. In a receiver birdies are a local problem and

Hi Walt, Others here have reported doing what you propose and had no ill effects. I intend to eventually do the same thing. 73, Bill KU8H -- bark less - wag more

Some additional data (sorry it's in french) about consumption trials on arduino boards (genuine and chinese) :

Thanks Folks, I will go ahead with my plans then, so far so good!!, I am having a great time, can’t remember so much fun since I built a Heathkit television in my senior year in high school, guess

I don't have anything that's driven by the AD8307, only the AD9850. However, the OLED doesn't care since it uses pins A4 (SDA) and A5 (CLK) for the clock and data lines for I2C interfacing. The data

Hi, new to uBitx, I've a problem already shown on some thread but more than a plaster on the wound I would like to understand the problem and reduce it. My 7805 get very hot after few minuts (already

I have my power output transistors on a large heatsink with isolators for each. Been using them for several months with digital and voice modes. Works well with no detectable issues. Joe VE1BWV

I have had the fine WD8CEC firmware on my ubitx for about a month, am running the 1.8 version. Today I just started noticing that the carrier frequency display tracks roughly the modulation frequency

Kees, after having some trouble I got the sketch from? Duwayne? (KV4qb blogspot) to play, even with a 0.96?? and 1.3?? I2C display. See

The frequency response of the second IF filters of the Ubitx vary from unit to unit depending also where the BFO is set. My unit for example is about 2khz wide filtering out frequencies below 700hz.

Hmm... It may be improper level of LO injection. On the transmit side, the mixer has _very_ strong input termination and LO termination. It will be interesting to study this. Mixers can provide

Would be interesting to pop the lids off the various TDA2822 parts, examine the die under a microscope. I'm betting the WX looks significantly different than an ST.

You think the WX might be a repackaged TA2822D meant for the SOIC8? I doubt it. I think the WX is a cheap copy that simply doesn't meet the 15v absolute max spec We had reports that there are clones

You missed my point Jerry. I am not suggesting 2822D. Please see the spec sheet I attached. It is a lower power version of tda2822. I think that die is being repackaged as TDA2822 in 8 pin DIP. It

Thanks, everyone, for the comments.? It is great information. Looks like I need to wait a little longer. 73 Mike KK7ER

I believe that should work fine. Given the significant power and the relatively low voltages, the impedance at the drain is quite low.? A little bit of extra capacitive coupling is not too

The four transmit filters we have are all low pass filters. The spur Allison found is below the operating frequency, so those filters don't touch it. When operating at 28mhz, the spur is at 45mhz -

Hello fellow constructors I have been thinking about using a common heat sink for the RF power transistors, insulated with mica washers of course and insulated mounting hardware. Would there be inter

Very neat Peter!