[ARC5] More -Whink and crystals.

[Kenneth G. Gordon]

On 4 Aug 2013 at 6:20, David Stinson wrote:

> You've probably said this before, but I missed it.
> How do you mount or hold the crystal in the solution?
> Just it just lay in the bottom of the container?

At the moment, I simply let the blank sit in the bottom of the container of Whink. I will "swirl" it 
a few times (carefully) , if I happen to think of it.

The container I am using is a short section off the bottom of a "foam" plastic drinking cup. I 
have marked it all around with skull-and-crossbones, and am very careful to keep it tightly 
covered with a piece of sheet-plastic with a weight on it. The stuff evaporates very quickly 
and is hard on the sinuses.

I am planning to build or buy an all-plastic very tiny "aquarium" or possibly a small clear-
plastic jewelery box. I have a very small air-pump which we have used with an atomizer. I 
plan to connect the air pump to the box through some plastic tubing so the air bubbles can 
agitate the solution.

I also plan to mount a small plastic mesh screen above the bottom of the box so the crystal 
blank can be reached more easily on both sides with the solution.

What I have been wracking my brain about is some sort of small plastic container that can be 
closed and opened, with a bunch of holes drilled in it, and of a size that will take one crystal 
blank. That way I can mark the container, and etch several crystals at once. However, I have 
not yet come up with a suitable container.

I will repeat: the Whink Rust Remover contains only 2% of HF, and therefore it is a bit "slow". 
However, that slowness makes it easier to not overshoot. Also, the Whink does lose its 
effectiveness after a while and must be replenished. But another couple of advantages to it 
are 1) it is cheap, and 2) you can buy it in grocery stores. Lastly the fact that the solution is 
only 2% HF makes it far less dangerous to handle than a high concentration would be. Even 
so, you do have to be careful with it.

When it is "new" the Whink Rust Remover etches the crystal about 70 cycles per minute. For 
instance, it took about 90 minutes to etch a crystal from 7000.410 KHz, to 7006.65 KHz. As it 
gets used, it takes longer, but I have not plotted that out.

In fact, the solution I used to move the above crystal was the same solution I had stupidly left 
another 7000 KHz rock in for over a day and ruined. As I said, it is now a 7070 KHz rock. 
Rats! I am NOT pleased! :-(

I counted up the crystals I have here that I can etch up into the 40 meter band: I have 92 
crystals for that band. The lowest frequency one I have is 5235 KHz. I also have some 
crystals which are above the 40 meter band. Some of those I can etch to cover 30 meters, 
and some I can etch to cover 17 meters by doubling.

I have not yet decided how far apart I need to make these crystals. I don't see the need for 
having them 1 KHz apart, but maybe I should do that. Maybe someone here will suggest 
something.

The nice thing about 40 meter rocks is that they can also be used on 20, 15 and 10 meters.

I know I have another, larger, batch of FT-243 crystals, but can't find that batch at this point. 
For a while, before they became popular, I was buying batches of "non-ham band" FT-243s 
for peanuts. Now they have all gone up.

What I really want to find are 80 meter rocks or some that can be etched up to 80 meters. I 
also want rocks which are on frequencies below 5 MHz to use for 30 meters. And 160 meter 
rocks are the most difficult to find of all.

I suppose I have given you too much information...but I have more yet. :-)

Ken W7EKB