Wednesday, August 13, 2008

little ideas

reducing sound through windows:

---double-glazed helps

---triple glazong adds very little extra suppression

---another layer 4 inches away helps a lot though

---layers that are different weight densities help a lot
(glass 1/8" and acrylic 1/8" <---1/2 the weight dens)
(glass 1/8" and glass 1/4" <----twice density)

---for low frequencies (truck rumbling, etc)
seal window well

little ideas

approx. energy in different batteries:

(radio shack alkaline, 2002)

aaa 1100 mAH

aa 2500 mAH

C 7100 mAH

D 14,300 mAH

9v (aaaa cells) 600 mAH

little ideas

How you can rank job opportunities...
add up scores of estimates in:

---compensation (pay/bonus/etc)


---environment (people, office, etc)


---skill growth

---interesting work topics

little ideas

business plans:
your average entrepreneur needs a 'business plan'
to get going. handy for thinking about projects too
very nutshell:

1) summary:
--bus. description (location/product/market,competition/mgmt)
--financial needs
--earnings predictions

2) market analysis (market/competition)

3) product (descrip / proprietary edge / comparison)

4) marketing strategy (overall, methods, pricing)

5) management plans (org chart, board, resumes, key people)

6) financial data
--2-year projection
--sources, sinks

little ideas

I made a headphone amp that runs off a 9-v battery
and powers stereo headphones off stereo line-level
cords. Each channel is like this, as you go through it:

---a 100K ohm volume ctl on the input
(center wiper goes to input)

---a 50 uF input capacitor (10 would be OK)

---the base of a 2n2222 transistor is biased via
(the capacitor feeds into it as well)

---the emitter goes to ground through 100 ohms

---the collector is fed by 9v through 33 ohms

---the emitter is tapped through 200uF for output to
headphone channel

Very smooth glassy-clear sound. You can put the output
of a little walkman phone plug through, and the bass will
open way up.


The best deal in audiophile super-fidelity
headphones is Grado SR-60s at about $70

Thursday, August 7, 2008

updates on items

---->The Sony ICF-38 now gets toted around the house,
on walks, and is used without a loop for AM-DX (BC-DX)
at night. The selectivity works wickedly well with fingernail
tuning. A great one. Might buy one for the parents' camp.

---> The 1-turn (10 ft dia.) AM loop hanging from the house
didn't work out. Too close to all the awful static from PCs,
washing machine, dimmer, CFL lights, etc...
Next try will have to be 15+ feet away.