New method for PCB making...

...At least for me.

I normally don't do much PCB, using the standard method or standard methods, but this time since there was a need to solder an SMD amplifier device it seemed that could be a good idea to do so. Just because I'm out of my normal shack I started to look for alternatives for the normal Iron perchlorate liquid and came up with a new product to dissolve the cooper. The method is explained elsewhere in the net by it's creator.

 Basically it's 50% of Hidrogen Peroxide (oxygenated water sold in pharmacies used as an disinfectant for small cuts on skin,, at least I used wen I was a kid) and 50% of vinegar with some salt to taste! Without the salt it would not work and you must be adding some so the process continues.

Here's the board before being cuted. The device to solder (PGA103+) is near the 1n5711 diode, big hum?

Had to buy an hacksaw for the job:


And now the mix, from time to time the board must be shaken and some salt added.

 The rest of the cooper part was protected with clear tape.

The final result:

 Does it pays of? No, except if you are in an island and really need to make a pcb....
and if you want to know I used normal white wine vinegar. Took me around 45 minutes from start to finish.
Now I still have to solder!

Have a lot of fun!

Restart

 After almost two month after arriving to this Island (Ireland) I decided it's time to restart my soldering activities.
Since I didn't had space to bring my shack with me, when I flew in, I opted to bring just a small container of hard to find components, what I didn't knew is that all electronic component are hard to find here.
After some search I found only one company selling electronics around and for getting things worst is one that nowadays is more focused in ready made stuff, oh well..., they still sell you a resistor, if its on their catalog....but you will pay premium price! I will never complain again on the prices back home!

Anyhow, after the initial shock I managed to buy some stuff need, other will have to be sourced in the Internet and back home.

here's my shack "equipment" so far:

Top row was bough yesterday, a soldering "station", cheap and according to a fellow ham, durable. Got also a spare sponge since the one in the kit is very small. Two pcb's for rapid prototyping and one for more definitive setup, also sourced a cheap knife on a pound shop for making traces on the pcb and to remove insulation from wires.
 Bottom row: On the left, the box of components that come with me on the plane and on the right two minicircuits rf amp in static protection on top of the letter that bring them. An ofter from a nice fellow ham living on the north side of  the island East of this one. By the way, there's no island to West, just a big pond...

I still need a multimeter, probably I'll ask for shipping me from home one of mine's since I have too many multimeter's, well I have too many soldering irons also but they are almost all junk...

Now the idea is to start building a new receiver, first the audio amplifier and rf preamp and then all the circuits in the middle! Easy!

Stay tuned and have a nice week!

EI/CT2GQV

Well, after 2 weeks in Ireland i'm starting to think if it's not better to ask for a local ham license.
For now it's not of much of a use since I still don't have a soldering iron to build a radio and the "Speaky" was to big to bring with me.

While I don't share some solder work here's some images from Cork and Ballincollig (were I am).

As the Irish say: Thanks a million!

New adventure

A new adventure...

Flight went well, sleep almost all of it and was wake up by the cabin voice stating the approach...

Now have to find a soldering iron but still on limited bandwidth to update the blog.

Have fun!

End block for a spectrum analyzer add on.

Is it preferable to have an spectrum analyzer for ocasional rf work or a nice scope and then make a spectrum analyzer add on module?

Well for me, and for now I'm going the path of the spectrum analyzer module add on, since a stand alone spectrum analyzer is far more expensive than any of my radios....you get the point. Some past experiments on a similar module were already made some blog posts ago

 by using the RSI from a AM detector chip, now I'm using another approach with the AD8307 logarithmic amplifier.

On to the schematic:

It's basicaly a "Bitx" 10 Mhz filter terminated in 50 Ohm (I hope, not measured yet)
connected to an AD8307 with about 45 Ohm input (from Analog datasheet)

On the right of the schematic there's an option for a common 10.7 Mhz filter from Murata (did not test this option).

Here's some signal "injection" for a preliminary test:


With the output from the "signal generator" (dip meter) 1 Mhz from the filter center frequency:

Without signal:
 
 And at filter ressonance:


The AD8307 is the SOIC version and after all was not that hard to solder, I removed some cooper from the board and lay'd there the IC, then soldered some wires to the necessary pins:


Will continue this experiments as soon as possible....that may take some time...

Until then, solder what you can... and have a nice week!

20m band module

20m band module:

Done, but the switching (pin) diodes are standard rectifier 1n4007, it works and for now enough.
I tried to replaced the original schematic varicaps by BB909 type I bought in bulk and.....works nice, although specs are a little different in terms of ratio, but not capacity.
The paint job on this BB909 is not their best feature and after scraping the paint a little bit I can see a diode similar to 1n914 and 4148. I suspect it's some re-branding by the manufacturer which is specialized in hard to find components.

30m band is in prep, oscillator crystal already in place but I suspect will take some time to finish this one....

The Speaky with 5 band modules (2 unfinished):

Also finished the antenna tuner with coil connections for the present "Speaky" bands: 40, 20 and 17m. It also tunes 80m if needed on my piece of wire antenna (something that resembles an dipole :).

Have a nice weekend!

In the mail

Arrived this:

For another generic power meter. This time I bought in SOIC form instead of standard DIP, it's a fourth of the price.

Meanwhile changed the the VFO coil on the 20m band module, still need to replace the 18.118 MHz crystal for the 18 Mhz one so I can use the lower part of the band. Now starts here:

Stay tuned!