Goodbye Radioshack!

On February 5th, 2015 the electronics retailer RadioShack finally filed for Chapter 11 protection under US bankruptcy law after 11 consecutive quarterly losses. Many stores closed as a result of this. Before they closed their doors forever, RadioShack blew out their remaining inventory with great discounts.

When I first heard of the RadioShack bankruptcy, I was not surprised at all. Nor was I bothered by it. RadioShack used to be the go-to place for electronics parts and state of the art electronics. But those times have been long gone. The electronic giant made the fatal business decision to shift more into the cell phone parket. Many of their employees lack knowledge in teh electronics area but will try to sell you a cell phone with every purchase. At least that was my perception. Towards the end RadioShack management realized their mistake and tried to re-align the stores with the maker industry. But just putting Arduinos on the shelf by itself doesn’t do much. The employees aren’t well trained for these kind of products and therefore RadioShack never really lost its image as a cell phone store.

With the closure of many stores and the chapter 11 bankruptcy an era comes to an end. I’m not sure if it the stores in their current state will really be missed.What about you, how do you feel about the RadioShack closure? Please leave your RadioShack related stories and opinions in the comment section below.

Here are some pictures of my final blowout shopping trips:

First RadioShack bankruptcy blowout catch.

First RadioShack bankruptcy blowout catch.

Second RadioShack bankruptcy blowout catch.

Second RadioShack bankruptcy blowout catch.

Pretty much cleared out store

Pretty much cleared out store

Not much left

Not much left

Links and Sources:

[1] QST: http://www.arrl.org/qst

 

Teledyne LeCroy Factory Tour Day 1, Post 1

This week I am at the Teledyne LeCroy factory in Chestnut Ridge, NY. Besides enjoying the cold, rainy and dark weather, I’m going to share lots of pictures and videos with you throughout the next days and weeks. If there are any questions you’d like me to ask during interviews or there’s anything in particular you’d like me to cover, let me know!

Here are a few pictures of this morning’s Factory tour:

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Tektronix RSA306 IF Frequency Verification

After posting the teardown video of the Tektronix RSA306 USB 3.0 Spectrum Analyzer on my YouTube channel, someone asked me to verify that the IF sampled by the Linear Technology 14-Bit / 125 Msps ADC is really at 140 MHz. Using the Tektronix MDO4104B-6 and a passive RF probe, I gladly did so.

With a 100 MHz, 0 dBm signal applied to the spectrum analyzers input and the SignalVu-PC settings set to 100 MHz center frequency, 40 MHz span, the signal at the ADC input looked like this:

Spectrum at the LTC2261-14 input with a 100 MHz, 0 dBm signal

Spectrum at the LTC2261-14 input with a 100 MHz, 0 dBm signal

So indeed, 140 MHz is our strongest peak. 20 dBc lower is a 28 MHz peak. Before taking the picture I of course tried a large span to make sure that there aren’t any relevant signals at a lower frequency. So the next test uses a 105 MHz signal still at 0 dBm.

Spectrum at the LTC2261-14 input with a 105 MHz, 0 dBm signal

Spectrum at the LTC2261-14 input with a 105 MHz, 0 dBm signal

So indeed, it seems that the LTC2261-14 samples the 140 MHz IF directly. How you ask? The answer is undersampling. The ADC is actually sampling at 112 Msamples/s. As a result, it sees an alias of the 140 MHz signal at 28 MHz. That’s all the magic happening here.

This probing expedition also yielded some pretty pictures that I would like to share. Enjoy!

Probing around inside the Tektronix RSA306 USB 3.0 Spectrum Analyzer

Probing around inside the Tektronix RSA306 USB 3.0 Spectrum Analyzer

Probing around inside the Tektronix RSA306 USB 3.0 Spectrum Analyzer

Probing around inside the Tektronix RSA306 USB 3.0 Spectrum Analyzer

Probing around inside the Tektronix RSA306 USB 3.0 Spectrum Analyzer

Probing around inside the Tektronix RSA306 USB 3.0 Spectrum Analyzer