wrm

This… is stupid

(IMO, of course. And Geek Alert)

MFJ-949E

This is the switch and tuner schematic for an MFJ-949E Versa Tuner II. Great little unit, with a built-in dummy load. It has a switch that selects the dummy load, then the three antenna connectors in pass-through mode, then the three antenna connectors through the matching network, and then the dummy load again… through the matching network.

Which means that if you want to tune into the dummy load, you have to use the setting all the way to the left, or you have to adjust the tuner to match the dummy load to the rig, using the switch setting on the right.

Now why would you need to match a 50 ohm dummy load to your rig? Insane. The dummy load switch setting on the right should connect straight to the dummy load, not via the tuner.

I have a soldering iron, I can fix it.

2017-07-15 by wrm Electronics Geek ZS1KE 0

40 Years

https://youtu.be/yHfLyMAHrQE

Dankie Oom Gielie.

2017-05-25 by wrm Geek 0

Early in-line memory modules

IMG_9817r

Predecessor of the SIMM?

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This comes from a piece of medical equipment made by the other S&W, Simonsen & Weel, Denmark, circa 1979.

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Each module has 8 x AM2808PC 1024-bit dynamic shift registers, driven by a DS0025CN two-phase clock driver. That’s one kilobyte of storage per module, and you have to keep on clocking the data around the ring otherwise the capacitors making up the memory discharge and forget.

It’s a lot simpler than a mercury delay line memory, but functionally it’s not that much different.

2017-04-13 by wrm Computers Get Off My Lawn 0

Perspective

How big does the Ark have to be for you to be invited along?

2017-03-30 by wrm Farting around 0

2017-03-22

12552771_1167524413278860_7728517169999734814_n

Now go away.

2017-03-22 by wrm Get Off My Lawn 0

Helping a friend move

(no, not bodies)

20170204

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Turns out we could have used a minivan full of Mexicans.

2017-02-04 by wrm Farting around 1

The Story

If you like Brandi Carlile’s The Story but you think the song is just a little bit too big for her, try Minniva Børresen.

2017-01-25 by wrm Farting around 0

Virgin no more

Windows30

I installed Windows 3.0 for the first time today* From seven 720 kilobyte stiffy** disks. And it worked first time.

* Windows 3.1, I’ve installed countless times. Windows 3.0, never.

** Yea that’s what we call them here.

2017-01-20 by wrm Computers Geek Get Off My Lawn 0

Krismis Kruger, Addendum

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Found a stowaway in our mosquito net.

His face was cold. His mouth trembled, asking: “Who—who won the presidential election yesterday?”

2017-01-07 by wrm Geek Kruger 2016.2 0

Krismis Kruger Day 15

Went out early, drove up to Afsaal to check (again) if the hyena had not come back. No joy.

But we did spot the morning drive vehicle parked in one spot for too long. So we went to investigate.

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One, maybe two lions, quite far off in the bushes. We were not there long before they left, direction Afsaal.

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Saw a large herd of buffalo on our way back to camp, this one had a nasty gash on the back.

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Packed up the camp, found two scorpions under Philip’s tent. Big pinchers mean (relatively) harmless, right?

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Right.

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2017-01-06 by wrm Kruger 2016.2 0

Close

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