Doomsday Rig

Everything technical about radio can be discussed here, whether it's transmitting or receiving. Guides, charts, diagrams, etc. are all welcome.
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sinus trouble
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Re: Doomsday Rig

Post by sinus trouble » Sun Feb 04, 2018 12:11 am

Some great ideas raised here!
The PIC I am using is the 16F84 and my compiler is ancient! MikroC seems a lot quicker with basic commands pre built, I have noticed others using simulation software alongside?

The BGY33 takes me back to pre internet days, one of the first real RF amplifiers for me published in a 1970s book I got from the local library!
Sadly I never got my hands on one!

Back to the basic LM3915 meter, the Dot/Bar mode would have significant differences in current consumption!
As it would only be a tuning aid? I could have a push button to activate only during tuning?
And possibly different modes for measuring initial battery power etc..

A little about the Russians too! The thing I admire is that throughout history they have consistently pushed boundaries yet at half the cost and complexity of the rest of the western world! Mistakes have happened? But not a bad track record!
I am as stupid as I look! :|

Albert H
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Re: Doomsday Rig

Post by Albert H » Sun Feb 04, 2018 3:26 am

One battery-powered rig I did had an LCD. This showed frequency (by default), but had a couple of associated push buttons ("select" and "hold"). There was a constant "battery" display - it looked like the "bars" display commonly used on mobile phones.

The first push of "select" switched to displaying forward and reflected power. There was also a bargraph for a sort of "analogue" indication of SWR, which was useful when adjusting the antenna match.

The next push of the "select" button switched to displaying modulation level - great for set up adjustment of the input attenuator and internal limiter. There was a numerical display of modulation depth as well as the bargraph, which allowed accurate set-up with tone inputs.

The next push showed Battery Voltage and Current drain. There was also over and under voltage warnings.

The final indication was of heatsink temperature with warnings if required, and a "Thermal Shutdown" message for overheat conditions..

Without any further button pushes, the display would change back to the default (frequency) display after 30 seconds. "Hold" would keep the display on whatever was being displayed until the next button push. The display was kept as simple as possible, so that it could be interpreted even by inexperienced users. Alarm indications would automatically over-ride the currently displayed information, There was also an optional alarm buzzer to draw attention to fault situations.

I thought that the whole PIC and display board was going to be expensive, by was pleasantly surprised when I found that I could get the board ready-made and programmed for $14 each from a company in Korea! All I had to do was add the sensor inputs and scale their voltage ranges to suit the ADC inputs on the PIC.
"Why is my rig humming?"
"Because it doesn't know the words!"
;)

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yellowbeard
no manz can test innit
no manz can test innit
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Re: Doomsday Rig

Post by yellowbeard » Sun Feb 04, 2018 10:42 am

Just to keep you thinking about it, 11 capacitors, 2 chokes and three coils...

Code: Select all

http://jhdzkj.tripod.com/40w-amp/20w-amp.gif
:lol:

Albert H
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Re: Doomsday Rig

Post by Albert H » Sun Feb 04, 2018 8:56 pm

Your link doesn't work!
"Why is my rig humming?"
"Because it doesn't know the words!"
;)

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thewisepranker
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Re: Doomsday Rig

Post by thewisepranker » Sun Feb 04, 2018 9:04 pm

It does.

Image

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sinus trouble
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Re: Doomsday Rig

Post by sinus trouble » Sun Feb 04, 2018 11:23 pm

Such a simple and quite beautiful circuit!
Thinking about it back then it was lucky I didn't get hold of one those cos the kind of driver I was experimenting with was horrific!! :lol:
I had to do a search on the BGY33 just for nostalgic value when I noticed that 'Moutolous' bloke has made PCBs for it? Pointless Observation :lol:

Getting back to the Doomsday rig! Whilst the RDVV/LCD style circuits have good aspects? I already have NRG exciters that work well for me, even in harsh conditions!
Although it still uses a PIC? In an emergency/Botched repair situation it will still work without the PIC!
The purpose of the display is just a basic tuning aid without DMMs, SWR meters!
Overmod is not critical if you just want to get a message out!
I am as stupid as I look! :|

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