R3tr0rad's Blog

“Look Ma” 12K5 Kit is back

r3tr0rad — Sun, 29 Jan 2012 15:45:19 +0000

In the Spring of 2006, almost 6 years ago, we designed an operating 12K5 oscillator that was crytal controlled and had output on 40 meters. It was submitted and written up in the May 2006 issue of CQ Magazine. It was inspired by ealier articles that introduced new hams to the old breadboard transmitters that used electricity directly from the household mains without any isolation transformer. Open wires and bare connections were used all over the board. Our little transmitter used a “space charge” vacuum tube which was designed for automobile radios in the early 1960′s, before transistors were production ready. This 12K5 tube used 12 volts on the filaments and on the plate circuit. Works great except the power output is very low. Remember, volts times amps equals watts, and, with such low voltage you just arent going to get a lot of power out. Power, whether at audio or radio frequencies, is under one watt. We also sell our vacuum tube audio amplifier with a 12K5 output tube, and , yes, the volume is just fine for a quiet room or headphones, but not much more.

We quit selling the little 12k5 transmitter kit when crystals became scarce. You see, we like to include the 40 meter QRP crystal in each kit. Well, for now, we are able to do it again. Please check eBay or www.pastimeprojects.com for purchase of these kits. The kit includes a wound coil assembly with link coupling, a small trimmer capacitor pre soldered on the terminal strip, a nice solid oak block finished by our Amish neighbors, and tested 12K5 vacuum tube, a great manual for step by step easy assembly, and clips, capacitors, sockets, resistors, wire and hardware to make this a fun project. You wont send CW very far on 40 meters, but distant DX communications was not the intent of this fun, learning kit. Please consider purchasing this little piece of history. Makes a great conversation piece for your shack. By the way, power can be supplied from your 12 vold dc power supply rated at one amp or more.

73 Glenn www.pastimeprojects.com

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

r3tr0rad — Mon, 09 Jan 2012 01:52:49 +0000

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

New Year Approaches

r3tr0rad — Mon, 26 Dec 2011 02:03:44 +0000

As we enter the last week of December, we look forward to the New Year. We have sold a few of our solid state amplifier kits on eBay with good results and great feedback.. The price was reduced on these kits for most of December, and hopefully, into January.. Some of the builders have sent links to their kits operating via video. You can follow these on our home page on www.pastimeprojects.com . We are checking with suppliers and our cost data to see if a permanent price drop would make sense. Meanwhile, these kits are fun, relatively easy to assemble, and work really well… At under thirty dollars, why not give one a try? 73 Glenn NN8G

Transmitter Crystals

r3tr0rad — Sat, 10 Dec 2011 01:08:19 +0000

Pastime Projects is going to change the format for selling transmitter crystals on the web site. We are going to list crystals individually along with their price so you can select which specific crystal you want.

The crystals will be sold with shipping costs included. Please consider this when you compare other sources for your crystals. The World War II style crystals we use in old homebrew, surplus, and amateur transmitters from the 1950′s and 1960′s were FT-243 types. These are roughly 3/4 inch wide, 3/8 thick, and 1 1/8 inches high. Pins are spaced just slightly under 1/2 inch apart. If you are buying crystals for the older handbook designs, or the commercially made tube transmitters of yesteryear, you should stick with the FT-243 type (or equivalent) crystals. This is especially true if you are using a one tube transmitter/oscillator. The older crystals can handle more current than the miniature wire lead type crystals generally sold for use in qrp transmitters.

The Pastime Crystals we sell have, for the most part, been checked in our 6V6 transmit/oscillator units for operation, output, and frequency. If you would like, you can email a request for this test to be performed for you at no charge here at Pastime Projects.

Please watch for these crystals to appear on the pages of our website www.pastimeprojects.com . 73 Glenn NN8G

Holidays Coming

r3tr0rad — Fri, 11 Nov 2011 02:08:40 +0000

Time change, colder weather, shorter days, and even a snowflake sighted here in mid Ohio! Here it is November already and time to prepare for the holidays. Cooler weather means more shop time and hopefully some production can be ramped up here at Pastime Projects. Stay tuned!

Tuna Tins on Sale

r3tr0rad — Thu, 13 Oct 2011 15:58:56 +0000

On our parts page of www.pastimeprojects.com we advertise tins similar to those that tuna fish come in at the grocery store. These are great for QRP and other projects and crafts where a small metal round tin with cover is needed for chassis building or other project. Ours are HUGE by comparison. They measure approximately 3 3/8 diameter by 2 1/4 deep. There is a special on eBay for one week – ending on October 19 – with an auction for a LOT of Ten of these tins for 99 CENTS starting bid!

Crystals – Vintage, Military, Novice

r3tr0rad — Wed, 14 Sep 2011 02:06:01 +0000

We are currently selling many older style crystals on eBay and, if you ask, through the www.pastimeprojects.com web site. We have many that are in the 80 and 40 meter CW and CW QRP current frequencies. Also many that are used to multiply up into the 14 and 28 mHz frequencies. Got a couple BC 610 crystals too. At least one of these is in the 75 meter AM phone frequencies. Have old Bliley ’round’ crystals, also most in the ham frequencies. Some are in the original boxes. Please contact us whether you are an interested ham, dealer, military collector, antique dealer, or museum. Now is the time to act. 73 es bcnu Glenn NN8G pastimeprojects@yahoo.com (Dont forget to use a subject so we recognise a valid email.)

Vintage Ham Band Crystals

r3tr0rad — Tue, 30 Aug 2011 14:19:03 +0000

From an estate we have aquired many crystals. Many FT 243 style, a couple that came from the old BC610 workhorses, and many old round types. These will all be cleaned, tested for activity in a vintage tube type Tri-Tet or similar oscillator, and checked for frequency. Since these are one of a kind, we will auction them individually on eBay. We will certify that each has been tested before shipping. We welcome your inquiry as to availability for your needs, whether as to style, frequency, pre auction price and so on. Yes, we have many that will multiply to 2 and 6 meters as used in the old AM transmitters. Speaking of AM, we seem to have many at the top end of the 75 phone band. Please don’t hesitate to contact us. This is a one time offer. As you know they dont make the old style crystals any more with the original crystal blanks sealed inside from 70 years or more ago. Better invest now.. pastimeprojects@yahoo.com Please include a subject line in your email .

Summer is Hamfest Time

r3tr0rad — Sat, 16 Jul 2011 14:47:19 +0000

Pastime Projects plans to display our products at the Findlay Ohio Hamfest again this year. The date will be September 11, 2011 as far as we know at this time. New product development and the newsletter release has slowed down a bit with the summer activities. We are looking at some improvements to the work place here if conditions and costs are reasonable. Please continue to look for our specials on eBay. We often clear out one of a kind electronic items that we have accumulated from years of collecting. Have a great summer. Write us and let us know what you are doing this summer. pastimeprojects@yahoo.com Please include a subject line . Glenn

June already?

r3tr0rad — Mon, 06 Jun 2011 01:41:02 +0000

We promised one of our customers almost sixty days ago that our little regenerative radio kit covering AM broadcast would be available by June first. While the radio is operating well beyond our hopes for a simple easy to build design, the delays are in the details. Perhaps we care too much about the style, the ease of operation, and the manual writeup, but we are betting that the end result will be worth the effort. Give us a few more days. Same with the newsletter. We hope to use that newsletter to give our readers the first introduction to this new receiver…. Best regards Glenn NN8G Pastime Projects.