Posts Tagged ‘boat anchor’

Pastime Projects rights to copy

July 10, 2018

The Pastime Projects (www.pastimeprojects.com) web site contains warnings about copyright
terms and conditions. This may frighten away those experimenters who are inspired by the
vintage makeup of our kits. That is the last thing we want to do! Please email us at
pastimeprojects(at)yahoo(dot)com for permission to copy or request copies of our materials.
We are “Makers” “do it yourselfers” handy men, or what ever you call yourself!
Let us hear from you! How can we help you?

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Use of light bulb dummy loads in Vintage Amateur Radios

May 29, 2013

We recently reworked a Johnson Viking Adventurer CW transmitter and an EICO 723 transmitter, both manufactured in the 1960’s. They can be seen at http://www.pastimeprojects.com on the Special Sales page.
A common failure of these transmitters was the power transformers.
They can overheat from current draw in excess of specified limits. This is often caused by not tuning the transmitter quickly or by mistuning and operating out of resonance.
Back in the 1950 and 1960’s we often used an incandescent light bulb for a load. It was cheap, and the resistance was close to 50 ohms or so required for the output of the transmitter. Tube type transmitters are a lot more forgiving from misstuning than solid state types. Never use a light bulb for a dummy load on your new
solid state rig! Choose a light bulb that has a wattage higher than the expected output of your transmitter. Watching the light bulb as you quickly tune to resonance will get you properly tuned without
too much time passing. Brightness is an indicator of power out. After tuning make sure you are not exceeding the recommended current draw. If you are, decrease the antenna coupling until you
are lower than maximum recommended power. Remember the old transmitter were rated in power input, now output. Output will always be lower. Input is plate current times plate voltage. This discussion is very simplified. Stay away from high voltage and high r.f wires. It’s hoped that it will help you see how to tune your boatanchor radio. Look for more detail in our newsletters and we may put out a video on disc or YouTube.
Questions are always welcome. Glenn for Pastime Projects.
pastimeprojects(at)yahoo(dot)com..

whats happening FT 243 crystals 6V6 6L6 tubes Dummy load kit.

January 9, 2012

We just discovered out little 5 watt dummy load kit disappeared from the web page.  www.pastimeprojects.com . We reinserted it on the parts components page and,  after checking inventory and starting another build cycle, we advertised the one in stock on eBay. It was sold before the ink was dry… So please take another look at this little kit as new ones go into our stock inventory.

It is a great way to catch up on a little bit of assembly and some easy soldering.  Large solder joints and heavy wires. Great project for the individual or a club.  Dummy load can handle up to 8 watts for short periods of time.  When the little box gets warm, just let it cool off a little. Great for qrp or cb rigs running 5 watts or so.  Monitor your signal, check power out, all without using an antenna and interfering with other stations.

Have you noticed the vacuum tubes and crystals we sell have a unique feature you wont find anywhere else?  We check them in actual transmitters for frequency and activity.   These will work in your ‘boat anchor’ or ‘homebrew’ tube type transmitter.  Each tube or crystal usually carries a certification tag.  If you want to be sure, just ask when you order.  They will work to your satisfaction.  Our FT-243 crystals are, for the most part, the original sealed units from the WW II period. They will handle more current than the typical small crystals sold today for qrp use.  If you are using crystals for 160, 80, 40, 20, 10, 6 or 2 meters, please email us at pastimeprojects@yahoo.com for the frequency range you are interested in.  We know some am rigs survive for 6 and 2 meter use, and we may be able to help.  We also have some high end 75 meter crystals that might be good for amplitude modulation. We simply dont have time right now to inventory all of the crystals so we will look for your specific needs as you ask. 

When you compare price,  remember is the other guy offering testing AND shipping and handling costs in his selling price?  Best regards Glenn NN8G