Until now he has been using my Fluke 87v multi meter with an old J-38 Morse key. When the Fluke is set to continuity it works great as the buzzer. I have many other meters with a continuity setting but only the Fluke 87v has a fast enough continuity tester to match my son’s practice speed.

I really wanted my Fluke back on my tech bench so we found a circuit he could build himself to use as the buzzer in place of my Fluke.

Alex is the host for this video and he seemed to have a lot of fun making the circuit and the video. GOOD JOB Alex!

This is the circuit Alex builds in his video to replace the beeping my meter was doing in his old setup.

He started off with a great introduction on why he was learning Morse code.

CLICK TO READ ALL —>:

Each week he has to convert his spelling words into a code for homework so he picked Morse.

Below is his old setup using my Fluke multi meter as a $300 buzzer.

In this book we found a replacement buzzer circuit to use.

Details found on page 103 of “Science and Communication Circuits & Projects” by Forrest M. Mims III.

Alex did give a nice overview of the circuit he was assembling.

A little soldering of the wires and components to a bit of perfboard but don’t forget the safety eyewear!

Alex had to drill some pilot holes to secure the circuit board and salvaged speaker with screws to a project board.

Testing. WORKS GREAT!

Using the 100K adjustable potentiometer (pot) Alex had some fun piercing my eardrums with high frequency squeals.

Video conclusion.

Thanks for joining!

One member volunteered to climb the tower to connect the strap and tow cable. This tower’s base is on a hinge so to bring it down you only need to remove some large bolts.

A local towing company volunteered their crane truck and a driver for a couple of hours. Thanks Apache Sands towing it was greatly appreciated. Some more volunteer members pulled on a counter rope and the tower is on its way down at the command of the tow truck operator.

The tower is lying down nicely on some old tires.

…

CLICK TO READ ALL —>:

…

This is a close up of the connection made to the tower for the tow cable.

Members go to work removing the old antenna and fixing the hard line that feeds the UHF/VHF signals to the antenna. In the below photo a member is bringing the new antenna.

The new antenna is now being mounted to the mast. The new antenna is ~18 feet, the mast is ~19 feet and the tower stands ~38 feet so the overall structure tops out at about 75 feet.

Below is the large copper grounding wire being connected to the antenna. This ground runs all the way to the base of the tower where it is then connected to ground rods.

We removed the last 18 feet of hard line from where the damaged point was to the top and replaced it with coax. There will be some signal lost but not enough to make any noticeable difference. Terry details how to attach the hard line connector which adapts the large hard line to a normal “N” style connector.

Install O-ring and some grease.

The first part of the connecter is now on and the outer copper has been flared by hand using a needle noise pliers.

The center conductor pin was screwed into the center of the hard line copper core. Some more grease was applied to the threads and flare point.

Terry then put the cap on and tightened up the connector.

The antenna we installed was a X500HNA made by Diamond and made in Japan.

The “N” connector and coax got some grease and protective rubber tape.

This is just a stainless steel sleeve that covers the connector at the base of the antenna.

The coax was lazy wrapped around the mast instead of clamped.

A loop of about 6 to 7 inches needs to be put in the coax just before going into the antenna to help reduce unwanted shielding currents that can exist at UHF/VHF and most likely for other reasons not explained.

The hard line that remained got nicely clamped to the tower.

Terry now details how to attached a new “N” connector to the new coax cable. He firsts preps the wire and slides on the crimp sleeve.

He sizes up the cut back on the shielding and exposure of the center conductor for the center pin.

Then Terry crimps on the new center conductor.

Then he puts on the outer part of the “N” connector over the shielding foil but under the braided grounding wire.

A simple plier is used to slide the crimp collar up and over the braided grounding wire.

Terry makes one more crimp to secure the collar of the “N” connector to the coax.

A quick check with an antenna analyzer confirms that both UHF and VHF are looking good even in this horizontal position.

The “N” connecter can now be attached to the hard line

Terry applies orange rubber tape around the “N” connector.

Then he applies generous amounts of black rubber tape to make sure no moisture ever gets into the connector.

The crane truck makes short work of brining the tower back up into position.

And we are done as soon as the bolts are installed at the base and the climber removes the cable.

Everything worked great with the repairs and antenna install. Thanks to everyone’s help the job was done in just about 2 hours.

If you are in the Mesa, AZ area you can listen in to this repeater and if you’re a ham you are welcome to use the SARC repeater even if you’re not a member:

VHF on 147.12MHz (+) PL 162.2Hz
<or>
UHF on 449.60MHz (-) PL 100.0Hz

Thanks for joining.

Todd

This video is showing my wiring install and shelving choices. I do cover reasons I picked curtain solutions and at the end is a tour of all my tech gear.

Below, behind me in the photo, is what my tech bench looked like in the past. What a mess! Very difficult to use or power anything.

The starting point of the video was when the shelf brackets were installed and so were 2 of the 3 junction boxes.

I’m routing the power from the old spot to this new junction box that will be above the first shelf and easy to reach. The left box is for the overhead light switch as well as the switch for the old corded power rail at my tool bench to the left of my tech bench. I cut the plug off the old corded power rail, tined the braded wire and secured the cord at the lower part of the junction box. The larger box on the right is for my GFI outlet and a switch to turn on/off all the power at the tech bench

Make sure to mark where the outlets will be on the back rail with “X”s and lines. Try not to put any screws in the marked areas unless you use very shallow heads. If you use large pan head screws in the “X” areas the outlet rail will not snap onto the back rail.

The back rails, boxes and conduit are ready. You don’t glue this type of conduit. Just push it together and use clamps to hold longer runs to the wall. You should plan for pulling wire. So leave a few open elbows or 90 degree joints with an access plate. My runs were short so I could just put everything up and pull wires later.

Below is the original 20A dedicated power feed to my bench and a 2nd wire that goes up to my overhead garage lighting just over my tech bench.

This is a close up of the junction boxes with conduit installed.

Great! All my wires are pulled. It was very easy because the runs were short.

The feed power and wires that will be used to switch the overhead lighting are now installed. I used quick wire clips “In-Sure Connectors” instead of wire nuts as you can see. It does make wiring a ton easer because you don’t have to fuss holding 3 to 6 wires, twisting them and then crank on a wire nut. With these quick wire clips you just work with one wire at a time. Much less fuss, trust me. The connectors are made by IDEAL and I get them at Home Depot. Search for “In-Sure Connectors” What is really nice is one size fixes all. The connectors work for #20 up to #12 AWG wires even at the same time. So if you have #12 supply going into a fluorescent fixture with #18 hookup wire the connectors still work just fine.

The left end of each power rail had a $5 junction adapter which was in addition to the $34 power rails. The overall cost is not bad when you have 300 feet of 12 gage stranded wire leftover from other wire install jobs. If I had to buy the wire I might have picked 12 gage 2 wire armored cable and all metal construction for the ground return. That would be less wiring and being I can buy that by the foot at Home Depot I could have had a series solution with less than 3 feet.

That brings up a planning error I made. I should have run all the power rails in series because that would have made the wiring in the one main junction box a lot easier. And the install would have looked a lot cleaner. But I chose not to because I waned to save the $10 for the two extra power rail junction adapters that would have been needed for a series run. All the outlets on both benches are on the load side of my GFI so I’m protected from a grounding fault. That is standard in a garage and don’t be cheap with the GFI at your bench!

All buttoned up and ready for a test! In the video you will see I do find a fault with one of the quick wire clips. One popped off when I pushed them into the main junction box. After reviewing my footage I found I had not put the wire security into the clip so that was my fault. Those clips work great if you are careful to insert your wires all the way to the back. The ends of the quick wire clips are clear so you can easily check your work.

Now everything is testing great including my under bench lighting which is plugged in at the end of the lower power rail. This way the under shelf lights come on only when I turn on the tech bench outlets.

Looking good, just needs gear!

My workstation ESD mat: I put the mat’s grounding wire in a hole and under the bench to keep it out of the way.

The grounding wire comes back up another hole near the power junction box for my bench. The black wire in the below photo. Being this metal junction box is earthed I attached my ESD mat grounding wire to a cover screw at one corner. Under the bench I just stabled the wire up and out of the way.

The bench is all loaded up with gear. At the end of my video I give a tour of my gear if you’re interested. Click the below image for higher res.

Thanks for joining.

Todd

That would be a saving of 228 watts in one chandelier and throughout our house the swap would have a total savings of 570 watts. Not a bad idea but the one we bought to test died in less than 2 weeks. It might have only been one week even.

I thought it would be fun to dissect it and see how it failed and maybe how it worked. Here is the video:

What better way to dissect electronics than with a hammer. “I got me’amer” – Photonic Induction.

It hammered apart quite nicely without any damage to the innards.

The pyramid was just a pack for 28 LED’s tightly packed using insulated standoff tubes. I was not sure at first if all the LED’s were in series or if there was some paralleling going on so the voltage could be lower to drive the LED’s.

It was not a complicated circuit. Some filter caps, two resistors, a diode and a SMD bridge rectifier.

Holly crawdads! It still works? I’m thinking the shrink wrap around the PCB was a bit small and it had managed to short the case to the wire feeding the LED’s. I also noticed one leg of the MB6S bridge rectifier IC was not soldered down and it had almost zero copper under the leg so that could have been causing an intermittent as well.

The Fluke says the PCB is putting out ~81V DC.

The AC ripper riding at the 81V DC offset was quite pronounced at 26V PP. But the LED’s didn’t seem to mind and the human eye couldn’t pickup any 120 Hz flashing if it was causing a problem.

The LED’s themselves draw 9.45mA. Not bad for 40 watts of equivalent incandescent lighting output.

I set my power supply to series mode to output my max at 63v DC. That wasn’t enough DC directly across the 28 LED’s to turn them all on so without any further circuit tracing I can tell the LED’s are in series being each white LED needs over 2v to be forward biased.

I must have been real close to turning the pack on with 63v DC because when I jumper across a couple less LED’s the rest of the LED’s came on. A little more probing with the 63v DC source went too far and “I popped’it” – Photonic Induction again I sure wish Photonic Induction wouldn’t have pulled off of YouTube. I loved that YouTube channel. The blackened LED’s are the ones I popped with too much voltage. It was fun while it lasted.

Thank you for joining.

Todd

Our ham radio club has used this tower and antenna for many years but it is now in need of repairs. The club wanted some footage to help plan the repairs. The buzzing in the shack is an over voltage alarm which will be fixed with the repairs along with a new antenna.

More information on the SARC website at: http://wb7tjd.org/wiki/Superstition_Amateur_Radio_Club,_Inc._147.12

I paid $79,95 for this from Adafruit.com when they first came out months ago.  Sorry for the delay but this did give me some time to really get to know all the features. I’m very happy with this USB microscope and have used it quite a lot. In the past I would have to put an eye loupe in front of my camera to take circuit close ups but this microscope does a lot better job. Inspecting very fine details and solder jobs is also tons easier with this microscope.

The box:

The USB microscope:

Setup and working:

I wanted to be able to have my circuits in my Panavise when using the USB microscope. I had a flex mic-stand from Radio Shack and some salvaged magnets from some old speakers. I hot glued one large magnet to the top of the mic-stand and another to the bottom of the USB microscope stand. With this setup I can easily switch between the desktop and my mic-stand when I need more flexibility.

An example of the close up of a (06 x 03) smd resistor using the photo button in the software. REAL NICE!!!

Below is my last example of using the measurement feature included with the software. It worked quite nice but I do wish it had more resolution like 0.001 would have been a better minimum than 0.01 for measuring close ups. This last photo was captured from my video of the laptop screen. I really should have uploaded a real screen shoot from the microscope because that would have look much better, like the one above.

Thanks for joining!

Somehow I or the crap designed circuit damaged one or more of the chips during part 1.

I started by testing my extra PWM chip (UC3843N) on a bread board. It was a new chip which was never used and it was testing fine until I turned the wrong knob and let out all the magic blue smoke. I took out the PWM chip that was in the control board since part 1 and it tested as bad. In fact Vcc was being shorted to ground. That explained a lot.

I ordered another PWM chips from Digi-Key and after installing it the controller and motor started working. I was having some speed regulation issues which I attributed to not having the heat sinks connected. At that time, which was the end of my video, I assumed the controller was functioning the best it could considering its poor design.

After delivering the motor and controller to HeatSync Labs one of the clever hackers there looked into the speed regulation issue which was not clearing as I thought it would once the heat sinks were mounted. He found another chip on the board that was bad, one of the op-amp chips. It was a chip I too had replaced over a year ago so something was killing the chips on the control board quite easily. This control board was such a pile of crap from day one.

It is working marvelously now so if you’re ever in Mesa Arizona swing by HeatSync Labs and try out their great little mini lathe. Maybe make yourself an aluminum chess piece or two.

Thanks for joining!

The three methods I cover are:
1) Manual desoldering pump at (adafruit.com)
2) 30 Watt Electric desoldering Tool at (amazon.com) or (elexp.com)
3) Solder wick at (adafruit.com)

If you don’t care to watch the video I will summarize below.

I have an exterior timer control that turns my Christmas lights on at dusk and off after 6 hours. I noticed they never turned off one day and thought I had left the timer control set to the ON position. But no, it was set to off 6 hours after dusk. I then set the selection switch to OFF but still it was on. I unplugged and plugged it back in but got the same problem. It was time to go to the electronics bench.

CLICK TO READ ALL —>:

NO SCREWS!! Damn now I have to bust this open. That alone might mean this is not going to be fixable. A few swift whacks with a hammer along the glued seams and it popped open. NICE! If I can fix it I can glue it up and be back to its water tight condition.

The board was single sided and all through hole construction. A quick glance around the board and I spied what looked like a fried transistor wired up to turn a 15A 125VAC relay on and off. The bottom of the transistor was all bubbled and I was sure it was a dead short causing the relay to be on all the time.

Above is a close up of transistor.

I removed the bad transistor using solder wick for one leg,

desolder pump for another leg

and for the last leg I used a 30 watt electric desoldering wand. This electric desolder wand is under $30 at most places and is a super greate tool IF YOU KEEP IT CLEAN! I used these three methods just to show the video viewers how each method works. The hints I give along the way are to set your solder iron to max when using solder wick and preheat the solder before applying the wick. I have also read that adding lead based solder to the joint in advance also helps the lead free solder wick up into the braid better.

This is the plunger in the desolder wand and it needs to be cleaned often!

This stuff will get on the o-rings and keep you from having a strong solder sucking vacuum.

I demonstrate how important it is to clean desolder pumps by taking one apart and using a bottle brush to get all the old solder scrap out. Then add a little Vaseline to the o-rings before reassembling.

Finally for the electric desolder pump/wand combo you must clean the hole in the tip with a wire that comes with the tool. If you follow these tips your component removal will be easy.

After getting the transistor out I take down the component number so I could lookup if it was a PNP or NPN and what leads were emitter, collector and base in the package. With this information I use the below transistor testing image to test if the transistor is good.

Photo from: “Using Your Meter” by Alvis J. Evans at (amazon.com) I did alter this image to be easier to read and use for DMM diode mode testing.

These images are really for using an ohm meter but if you put your DMM in diode test mode you get the same test except you’re testing the PN junction between the positive and negative DDM test leads instead of a straight up resistance. Where you see “LOW” you should get a forward bias diode junction pass on your DMM indicating a very low electrical resistance and where you see “HIGH” you should get OL on your DMM meaning “open loop” junction or very high electrical resistance.

If your type of transistor, NPN or PNP, fails one of the tests in any direction then it is bad and needs to be replaced. Please note that this is not a complete electrical test of a BJT transistor. A transistor can have other issues like high leakage and in circuit modes of failure that are beyond the scope of what I want to cover here. But if it fails this simple test it is bad and you can confidently know you have to replace the transistor.

My transistor passed with flying colors! So my problem was not this transistor and closer inspection revealed the melted plastic by the component’s legs was just some glue used to seal the case.

Nothing else controls the relay on my board so it must be the relay itself. I looked up the relays datasheet on the internet and found its pin out configuration then tested between the in and out of the normally open (NO) pins.

Sure enough it was a dead short so the relay’s contact points must be fused together.

Just for a bit of fun I used my Dremel tool and cut off the plastic top of the relay to see the failure. Sure enough the points were fused.

I popped the relay’s contact points apart and cleaned them up with some metal grade sandpaper. After tested the coils I soldered it back into the circuit along with the transistor I removed.

A quick test with my radio as the load showed the timer control was now working great!

I don’t want to put the repaired controller back in service knowing the relay has already had such damage so I will order a suitable replacement the next time I make a bulk parts order. For a couple of bucks I will have my Christmas light timer control back in service and not in a landfill.

UPDATE Dec 24th 2011:

My replacement relay has arrived. I dropped it in, sealed the box with hot glue and put it back in service. It is working perfectly. I replaced the relay with a 10Amp instead of the original 15Amp but that is just fine for my Christmas lighting plus it was cheaper at just $1.75 USA. The new relay was SPDT (single pole double throw) so I had to snip off the NC (normally closed) pin.

Thanks for visiting and don’t forget to subscribe to my YouTube channel if you like my videos.

A representative from Farnell contacted me and asked if I wanted to review some products. I said, “Sure, free supplies for my lab!” Actually, I found out that anybody can sign up for their product “Road Test” program at Element14.com but not everyone is selected. Farnell is a European company and known as Element14 in Asia and Newark in America (online catalog). But they also have a nice online community site at Element14.com/Community where you can get to their “Store” for your region.

For the “Road Test” I chose to review some different test lead management hangers made by Pomona. I have quite the mess of jumpers, patch cables, DMM probes and oscilloscope probes hanging on my peg board behind my lab bench. That is not a good way to store these and they are very difficult to access on peg board.

I selected two sizes with two different mounting options for this review. The Pomona model 1508 with 14 slots at 0.21in (5.33mm) opening is great for jumpers, patch cable and test leads. The 1508 model needs to mount using screws.

<photo 1508>

I also got the Pomona model 4408M with 8 slots at 0.32in (8.13mm) opening with magnet mounting. The 4408M is nice for oscilloscope probes and larger items.

<photo 4408M>

I was quite disappointed to find that you lose two slots for the magnet mount because they just bend the outside prongs down and add stick on magnets. This magnetic option drops a model 4408 with 10 slots to a 4408M with only 8 slots. If I had known that I would have got the model 4408 and just added my own magnetic plate. The photo for 4408M at Neward.com is curretly wrong and shows the model 2708 without bent prongs.
The magnetic option was not strong enough for the thin metal in my garage door anyway so I bent the two extra prongs up and used the screw mounts.

You can fabricate your own test lead hangers but at these prices it just makes sense to buy.
1508 is $17.53 USD (at the time of writing this it is on sale for $12.46)
4408 is $14.65 USD  (at the time of writing this it is on sale for $10.43)
4408M with magnet mount is $32.13 USD  (at the time of writing this it is on sale for $23.46)

Here are the after shots of my lab. WOW these hangers sure helped clean things up and I have already found it much easier to find and select items.

I even found some lost jumpers and micro hooks. I thought they were gone forever but were just under the pile of cables hanging on my peg board. I will not be losing track of such items anymore!

I guess I will have to get one more 1508 because I have so many jumper cables. I may even get their biggest hanger model 2708 with 9 slots at 0.45in (11.43mm) opening for my PC power cords and wall warts.

Thanks for visiting.