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It appears that I am ready for retirement.....

Goggle thinks that I am over the hill.

Your categories
Below you can review the interests and inferred demographics that Google has associated with your cookie. You can remove or edit these at any time.
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Arts & Entertainment - Music & Audio - Radio
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Computers & Electronics - Electronics & Electrical - Data Sheets & Electronics Reference
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Internet & Telecom - Communications Equipment - Radio Equipment
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Law & Government - Public Safety - Security Products & Services
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Reference - General Reference - Calculators & Reference Tools

Your demographics
We infer your age and gender based on the websites you've visited. You can remove or edit these at any time.
Age: 55-64
Gender: Male

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How did I find this?  I heard something on Public Radio yesterday while I was in the car. So of course I googled the info and found:  http://www.google.com/ads/preferences/

If you go there it will show your info and give you a change to change some of it.

So how did Google do:
  • I like movies and music
  • I am a professional IT Architect and amateur Electrical Engineer
  • I spend time looking at Internet & telecom related items and I am an amateur radio operator
  • I like guns and visit the target range on a regular basis
  • I use online electrical calculators for projects & do a lot of online research
  • I am not 55-64... I am 39.
I would say that they had it about 83% correct. From a marketing point of view they completely blew my demo because they were ~20 years off the mark on my age.  --I have a couple of years before I need to think about AARP membership, but thanks for the thought Google.


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Amplifiers at the workbench

I decided to go back and revisit a simple Class AB amplifier circuit based upon an NPN and PNP bipolar junction transistor that I worked on a couple of weeks ago. I am not sure what happened but I lost the magic and was not able to reproduce the gain in the circuit. <sigh>

After a bunch of messing around I grabbed a prototype Class A amplifier circuit board that I built back in February 2010. (It is even on an etched board)


The circuit is not very efficient since I am using about 190mA of current @ 12vdc. It is very much a Class A circuit with small signal parts but it has some gain. (The extra resistors are tweaks that I made 20 months ago to tweak the bias.)


If current is not a concern then this is generating 250-400mW of power with the RF drive that I would expect from a AD9851 DDS. Since I am using plastic NPN parts I have a heatsink on the final transistor (it was pretty warm to the touch.)

When time permits I will need to come back and design a new set of gain stages that are more efficient. Class A is a simple but expensive way to generator power. I need to think about Class B or Class C stages.

73 de NG0R