Teardown of a SMART UF-55 Projector

My workplace was throwing away an old SMART UF-55 DLP projector. The projector had many stuck mirrors and the lamp had already surpassed the rated useful life span. I had always wanted to take a look at a DMD chip so I decided to take it home and do a detailed teardown. You can find my video of this teardown towards the end of the post.
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Lambda LQ-521 Power Supply Teardown and Repair

I bought a non-working Lambda LQ-521 linear power supply on eBay a couple of weeks ago. Usually I avoid knowingly buying something that is broken unless I am certain that I could obtain parts for it at a reasonable price. But buying broken linear power supplies is another story as most of the problem can be fixed with readily available components.
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RSA SecurID Teardown

I did a teardown of an RSA SecurID many years ago (you can see that post here). In that teardown, it was an older generation (SD600) of the RSA SecurID. In this post, let’s take a look at what’s inside the newer SID700 series RSA SecurID token. A short video of the teardown is included towards the end.
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DTM0660 Datasheet Translated

I have received quite a bit of positive feedback since I wrote about the hacks on DTM0660L based multimeters last time. So I went ahead and translated the original Chinese datasheet into English and the PDF datasheet is linked below:
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Hacking DTM0660L Based Multimeters

In my previous post, I did a review of the 6000 counts ennoLogic eM860T true RMS multimeter. This meter is based on a signal chip design using the versatile DTM0660L DMM chip. Besides the ennoLogic eM860T, several other multimeters such as UNI-T 139C, Velleman DV4100, Tekpower TP40 etc. are also based on the same chip.
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Quick Review of the ennoLogic eM860T True RMS Multimeter

I picked up an autoranging True RMS multimeter from ennoLogic a couple of weeks ago. Before this purchase, I actually had never heard of ennoLogic. But the design and spec of the meter looked quite good and the selling price was not bad for a 6000 count meter at all. So I bought one to try out.
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Teardown of an 8-10 GHz RF Isolator

I did a teardown video of a microwave range (8-10 GHz) RF isolator last week. As a follow up, I will post some of the high-resolution pictures I took during the process here (click to see larger images).
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Teardown of a Tektronix 2465

Today at a time when digital storage oscilloscopes (DSO) are almost ubiquitous, analog scopes like Tektronix 2465 remain popular among many electronics hobbyists, especially among amateur radio operators who routinely work with high frequency circuits. I got my 2465 from ValueTronics. For those who haven’t heard about them, I would recommend you check them out as they have a large selection of used test equipment at reasonable prices.
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Keithley 706 RTC Upgrade – How to Make Any Clock More Accurate

The builtin real-time clock (RTC) in my Keithley 706 works rather nicely as a clock in my lab when the scanner is not in use. The 7-segment displays are big and clear and they are two dedicated displays for the seconds which comes in quite handy. However the main drawback of this auxiliary clock functionality is that, well, it is not very accurate. It is rather annoying when I need to adjust the clock every couple of days to make sure it remains correct.
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Reverse Engineering a Wavetek OCXO Board

I bought a Wavetek OCXO board a long while ago. My original plan was to remove the onboard crystal oven to replace the broken OCXO in my HP 5350B. But since I later managed to fix the original OCXO , this board had been sitting quietly in one of my component bins collecting dust.
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Building A Tracking Generator

In this blog post, I will show you how to build a 0 to 5.8 GHz tracking generator for the HP 8566B 100 Hz to 22 GHz spectrum analyzer using off-the-shelf components for under $100. Although this tracking generator is specifically designed for my HP 8566B spectrum analyzer, the method discussed below is applicable to pretty much any spectrum analyzer that has an LO output (typically the 1st LO).
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Tracing Filter/Oscillator Frequency Response Using Spectrum Analyzer and Signal Generator

In this blog post, Let’s take a look at how to measure a filter’s frequency response using a spectrum analyzer and a signal generator. Typically, a tracking generator is preferred for this kind of scalar network analysis as its center frequency is in-sync with the frequency the spectrum analyzer’s bandwidth filter is currently tuned to. But with a good signal generator, we can manually sweep across the desired frequency range and obtain similar amplitude versus frequency measurements.
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AM/FM Demodulation Using HP 8566B Spectrum Analyzer

In my previous blog post, I did a quick teardown of my HP 8566B spectrum analyzer. In this post, I will discuss how to use a spectrum analyzer like this to demodulate an AM or a FM signal. A video including the theory and a few experiments is linked towards the end.
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Some Pictures of My HP 8566B Spectrum Analyzer

The latest addition to my lab is an HP 8566B spectrum analyzer. This isn’t just any spectrum analyzer, it was perhaps the best spectrum analyzer money could buy back in the late 80’s. While it was discontinued in 1997 and has long become obsolete, its performance remains quite impressive even by today’s standards and still rivals that of many of its modern counterparts.
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ESR Measurement Using Multimeter and Function Generator

Capacitor ESR (Equivalent Series Resistance) measurement is very useful in diagnosing issues with power supplies. In linear power supplies, a high ESR filter capacitor may cause excessive ripple current on the voltage rails and can cause the capacitor to overheat due to its increased resistance. In low dropout linear supplies, the ESR of the output capacitors affect the loop stability and excessive ESR in these output capacitors can make the power supply unstable, which in turn can lead to out-of-tolerance voltage being applied to the load and could cause future damages. In switching mode power supplies, the ESR of capacitors are even more critical. In this blog post I will discuss how to measure the ESR of a capacitor using a function generator and a multimeter. A short video on this topic is also included towards the end.
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