Tube transmitters

00. Other articles where Transmitter is discussed: communication: Linear models: … five elements—an information In Lee de Forest: Invention of the Audion tube. 40M QRP Transmitter Using a 6CU6 Tube: This is a simple QRP transmitter modeled after a schematic from and OLD ARRL handbook. I'm a new forum member and will try to post some more of my projects. This kit includes Amish prepared oak slats and end blocks. A simplified AM transmitter circuit is shown in Fig. Few transmitters use the tube which was once considered expensive. It includes mainly tube transmitters (sometimes referred to as "hollow state") of all power levels -- from commercial AM & FM broadcast, shortwave, utility and military; to transmitters converted for the Amateur Radio service. A typical power oscillator (PO) minimalist single tube transmitter of reasonably good compromise between complexity, cleanliness, repeatability, and reliability  The early Audion (triode) tube is visible at right. TCO-5808R6. 939. 1. really 5 watt AM tube type transmitter plan This schematic, parts list and instruction sheet come from 1973 and offer a simple, robust three vacuum tube transmitter circuit that might make a nice project. The add-on was a simple one-tube short-wave transmitter leveraging the same power supply already available in the receiver. com Phone: 303-939-9336 Toll-Free: 800. Vintage 1950s US Army Signal Corps military vacuum tube radio transmitter unit. 8977 A copy from an old italian magazine of amatorial electronics, proposing an add-on for tube receivers. 3) The Original Frank Jones 10 watt, Push-Pull, Crystal Controlled, "Beginners Transmitter" from his book, "The Radio Amateur Newcomer", first printed in 1935 or so. The best over-the-air TV & radio broadcast transmitters available, plus turnkey solutions for public safety communications. But many fondly remember their first homebrew transmitter and its hard to forget warm glow of a vacuum tube. 2) A Push-Pull Self-excited Oscillator Transmitter of early design. heptode). A Two Tube transmitter. The 4 triode tubes, connected  This little transmitter came about as a result of my interest in vintage radio receivers, and the lack of anything worth listening to on the AM broadcast band ( 540  11 Apr 2020 Dual section tubes are much more common than triple section tubes. A typical power oscillator (PO) minimalist single tube transmitter of reasonably good compromise between complexity, cleanliness, repeatability, and reliability would have every component serve some critical function. A few years ago, a large number of these tubes were released from Air Force surplus and the price is now more reasonable. All modern transmitters, even high power ones, do work with transistors and other semiconductors. 172-175 This crystal controlled transmitter for 80-, 40-, 20-, 15-, and 10-meters uses a 12BY7 and a 1625. Mar 25, 2017 · Fifty years ago, the March 1967 issue of Electronics Illustrated carried the plans for this simple 40 meter CW transmitter. May 28, 2017 by Jenny List 23 Comments It is extremely easy to make an AM transmitter with a single transistor or tube, Tube Transmitters/Receivers. 70 cm, 2 or 6 meters. World War I led to rapid development of the new technology for military purposes, and  Zero Flow Tube for 30 Hz Coil Drive Operation. Low-voltage Transmitters. ARS Electronics Wholesale Electron Tube Distributor Since 1947, replacement new transmitter tubes and rebuilt transmitter tubes , replacement industrial microwave and magnetron tubes, tubes for radio frequency (rf) heating including rf plastic heating, rf vinyl sealing, rf welder also audio tubes for guitar amplifier electron tubes and audiophile amplifier electron tubes also aircraft even work. 2-tube QRP homebrew transmitter First things first: SAFETY- When you play with 5 V and 12 V solid state circuits almost exclusively, you may lack an appreciation for the danger associated with working with 250 volts, or even 120 volts, either of which can be lethal. A single 6U8A tube is used for the RF signal path, it contains a triode and a beam pentode in a 9 pin envelope. A transmitter designed for parrots should in- clude a protective metal case (brass) and metal crimped tubes (brass or copper) to protect the base of the antenna  This page is a detailed description of my 6CL6 and 807 valve transmitter. Construction. After using my improved 3 tube superhet in the 2001 AWA OT CW contest I felt the need to improve my 6L6 transmitter. However, the coils had apparently been made for a different purpose since the plug connections did not match those of the 6SN7 transmitters. There I found a 8. It uses a pair of 6L6GC tubes in Class AB1 push-pull generating between 15 and 20 ISS TR-6000 HQ 5. c. I changed gears, put the metal chassis and case away, and went up to the kitchen. : TWT, pronounced: “twit”) are vacuum tubes used as high-gain, low-noise, wide-bandwidth microwave wideband amplifiers. F. 219 Rules with variable-length coaxial cable in its approved design. AM solid state transmitters are more efficient, but also more expensive. Fred Nachbaur's Goldberg! A -revisit-with new circuit updates! One Linear Transmitter! Apr 25, 2020 · This Playlist is a collection of vintage radio and television RF transmitters gathered from around YouTube. Analog Output Range. 5" x 13" wooden breadboard with nicely turned edges. QSO with LA5FH in Larvik and LA9WNA in Skien. A Tube AM Transmitter In A Soup Can. Delivers a Bluetooth signal over 164 ft. Maybe its the glow of the tubes or the heat they produce. Below is the schematic diagram of the transmitter. Transmitters. Works with both RCA and digital input and output connections. Since its intended purpose was as a converter for superheterodyne receivers, its output power capability is quite low; in practise, about 3 milliwatts Gold plated transmitting tube made by ITT available at a fraction of original cost. 1 each, 35C5 beam power tube (the power amplifier tube in the MOPA) Note: this tube is designed as an audio output tube with a power output normally of about 1. I thoroughly enjoy their symetry and beauty. Current Design. This transmitter will give a newby a place to start! https://www. 00 Wireless Differential Pressure/Pressure Transmitters Yokogawa offers a complete line of ISA100 compliant pressure transmitters. k. Custom Search. We've assembled one of the largest selections of ham radio transmitters for sale in one place making it easy to find what you're looking for. It is a wise safety feature and prevents the wiring harness from going up in smoke should a tube filament short. Two tube CW transmitter. Tube-based transmitters must have power applied in the proper sequence, with the filament voltage applied before the anode voltage, otherwise the tubes can be damaged. The transmitter here is a homebrew "one tube" crystal oscillator. The line includes transmitters that can measure differential pressure, absolute pressure, and gauge pressure. They're approximately a quarter of the size of the miniature B9A tube  Measuring Tube and Pipe the Easy Way with VTube-LASER Connection to these measuring centers: HEXAGON Absolute Arms (Formerly ROMER arms); FARO . I modified the pin-outs of the coils to match the transmitters. A CW transmitter conveys intelligence in the form of Morse Code dots and dashes by turning on and off the transmitter. The set ran directly off AC power, with a transformer supplying 120 volts B+, rectified through two silicon diodes, as well as 6 volts for the filament of the single 6AQ5A tube. It uses a 6146 in a Grid-Plate circuit and puts out about 15 watts running straight thru on 80 or 40  This CRMX W-DMX interface can be used as a wireless DMX transmitter and receiver. Although it works very well as is, I decided that the design could be improved and simplified, by using a tube having characteristics specifically suited for the various functions. 50 kit/$259. It is built on a 8 x 8 inch baking pan that I picked up at the grocery store for $2. RCA Ham Tips. The only difference is that the modulator section is not self oscillating. Ham Radio Museum; E. You assemble with supplied instructions and brass plated flat head screws. com. This area presents radio-related building projects, a little bit of everything, from transmitters and a shortwave receiver, to nifty radio add-ons. V2a and V2b perform the same controlled carrier amplitude modulation function as previously described in The Improved 1-Tube AM Transmitter. It receives the carrier signal (already phase modulated) from the output of V1b. 782. With your cassette tape player, phonograph or high output microphone, this one tube transmitter becomes a miniature AM broadcasting station, patterned after the 1939 Zenith model S-7000 Wireless Record Player. It uses a 12SA7GT output tube. W-DMX CRMX transmitter receiver Titan Tube Film Lighting  Tubes don't fail catastrophically. . Dec 13, 2017 · For many years, AM transmitters used vacuum tubes for the power amplifiers and for the driver circuit. Tubes for industry, music, ham radio, the audiophile. Maybe not the proper place to place this thread, but I am wondering. The tubes used in this transmitter is a 6J5 and 6SA7 that operates at around 1400kHz on the AM band. We're getting close but there are still a few holes in the collection. The coils that were sold with the transmitters were nicely constructed from old 4 pin tube bases. of using a direct-digital synthesis. Also, some brands of transmitter are more complicated and require a higher level of understanding than others. A Radionette amplifier from the 50’s is power and modulator for the 6L6 transmitter. This is my first test of the 6L6 station. Be prepared and able to communicate in case of emergency with the largest selection at eBay. Using a 6C 4 tube, you can build a 4 W transmitter that operates in the range between 88 and 108 MHz. Unlike GE Ham News, this isn't quite a complete set of the RCA publications. Assemble on a 4 inch x 6. 5 watts. The 35W4 (x 2), 12BA6, and the 35C5 tubes’ filaments wired in series came to a total of 117 volts. Tube transmitter definition is - a radio transmitting set using a tube generator. This circuit combines the functions of oscillator and amplifier into a single tube, and provides Mar 28, 2018 · HART 25 ,One tube transmitter , HART Transmitter , QRP Transmitter QSO with my friend in Mishawaka Indiana a distance of 1200 miles on 80 meters CW what a thrill with 5 watts from a one tube Great deals on Ham & Amateur Radio Transmitters. It's a single-tube 7W CW transmitter, shown here with the 80M coil in place. The tube is a 6T9 Compactron triode-pentode. Results 1 - 48 of 100 Great deals on Vintage Ham Radio Transmitter. A 6AQ5 tube (V 1) is used in a crystal oscillator circuit. I really joined this forum to learn about DX crystal radio receivers, but I like tube gear too. Care and Feeding of Power Grid Tubes (Eimac/CPI): an excellent resource for the  11 Sep 2019 “C” and “Spiral” shaped Bourdon-tubes are typical examples. transmitter with full break-in (QSK) capability. Allows the insert to be exchanged during operation. The design of a one-tube (or one transistor) transmitter is a compromise involving power output, keying, and the effect of antenna coupling on operation. The final RF amp tube is a Raytheon 4D32. Series 607 ±0. (Note that 117L7 and 117M7 tubes are interchangable. tubesandmore. Discussion. The "Novice Special" Transmitter Tubes are a dying technology. Since the pressure required to displace the liquid is determined by the depth of the fluid, the transmitter output indicates the fluid depth above the open end of the sense tube. a common one-tube transmitter using a 12BE6 pentagrid converter (a. The top of the line is  6 Feb 2018 Table of Contents for Free Antentop Amateur Open Book. 0"w x 15. Traveling Wave Tubes (abbr. com/products/K-488. That is, the output (tank) circuit, consisting of coil L 1 and tuning capacitor C 7, is isolated from the d. Introduction. May 14, 2017 · The transmitter is of the "MOPA" design, being a main oscillator (using a 211 power triode tube) followed by a single PA stage (also a 211 tube). 1) Here is some data that Kees Talen took while attempting to find a proper tube to use in the low-voltage transmitter he is trying to design and build. We carry over 5,000 radio and vacuum tubes in stock every day and we ship world wide. 6L6 transmitter, bottom view. Browse the latest inventory of new, used, and vintage amateur radio transmitters and equipment available here at auction prices. I first built circuits with transistors that were  Tube AM Broadcast Transmitter Kit with plug-in Medium Wave coils. I call this the Tinderbox. The transmitter was built into a 3"x4"x10" aluminum utility box. The oscillator tube is keyed by a high-power dc pulse of energy generated by a  AM tube transmitter for 10m. A TWT is capable of gains from 40 to 70 dB with bandwidths exceeding two octaves. 0"d Approx. Select a valve cartridge if desired that matches the range of the flow tube. It produces 265VDC for the driver section of the transmitter, 500VDC for the power amplifier tube and 6. 0 Low Power AM Transmitter; Vacuum Tube AM Transmitters: There are plenty of radio enthusiasts who use these transmitters, from antique radio collectors to those who are fond of vacuum tubes. Quality of electronic  manufacturer of tube based high power RF transmitters used in the susceptibility testing of military aircraft and ordinance. Of course if you were to break a bunch of them and eat the cathodes, there would be danger. Transmitters may be damaged if operated without an antenna, so protection circuits must detect the loss of the antenna and switch off the transmitter immediately. If you ever wondered how those early radio and wireless transmitters from the 1930's  In addition, it enables you to retrofit to antenna matching systems previously fed by a vacuum-tube transmitter and modulator-determined modes. Power amplifier - 6L6. (DDS) VFO with a vintage tube-type transmitter. The 0D3 is an older type; I've never encountered one that had the radioactive marking on it. Louisville, CO 80027 sales@inovonics. The amount of material in the high-reliability 0B2WA tubes is tiny, and so is the danger. An Inexpensive 75-Watt Transmitter The Radio Amateur's Handbook, 1964, pp. 25"h x 21. The exterior of the transmitter is little changed from 1963 in this recent photo. GV Series Premium HD Radio-ready, high power transmitters: 3 kW to 80 kW NV LT Series Outstanding efficiency at exceptional value, & optional HD Radio: 3. AM tube shortwave transmitter with 6BH6 (oscilator), EL84 (buffer), 6L6GT (clamp) and 4 x 807 power amplifier. Choose the appropriate 65 mm or 150 mm correlated flow tubes, for air or water. Let us assume first that there is no audio signal. The first question I ask, when dealing with an RF problem in a tube-type transmitter  This series of small transmitters is designed for glue-on application to bats, birds, Examples of tube placement: Tubes will slightly increase length and weight  Reliable and long-term protection of the temperature sensor from rough process conditions. Transmitter Calibration. 80/40 meter CW Transmitter  In this transmitter one stage or tube, usually a magnetron produces the rf pulse. Fast & Free shipping on many items! 6L6 TRANSMITTER Here is my newest transmitter. ) In a single envelope, this tube combines both a diode and a pentode. The result is a 40 and 80 meter 20 watt high level plate modulated AM transmitter. The PA is then amplitude (plate) modulated using a Aug 21, 2011 · The schematic diagram shows the circuit of the transmitter. The tube was ideal for a simple transmitter, since the filament ran directly off line current, and the envelope contained a rectifier and beam-power tetrode. The DC high voltage connects to the PA tube through the modulation transformer. 30%, 4 to 20 mA or 1 to 5 VDC Signal Fixed Range Pressure Transmitter is a low cost, fixed range, stainless steel transmitter. Series 636 Stainless Steel, Explosion-proof, Accuracy ±0. One of the BBC's first broadcast transmitters, early 1920s, London. Below you'll see that I installed a pre-amp daughter-board. A shunt-fed plate circuit is employed. I use a BC-348-N as receiver. 00 3d 20h This ham band 80 -10 five tube (6BA6, 6U8A), two transistor receiver includes a 100-kHz calibrator. All parts and instructions included. As you can see from the schematic below, there is nothing unique about the circuitry in this two-tube 40-Mter crystal-controlled transmitter. Tube Transmitters 1920-1980And Linear Amplifiers, Transceivers, Modulators, Tuners, VFOs & more This article contains a lot of test data and graphs, and shows quite clearly that of the tubes tested, the 6AG7 is by far the best choice. If you have one of the missing copies, please consider scanning and sending the images to me. Taylor Ave. After building it using the 12SA7GT tube I modified it to use one of 3 different output tubes either a 12BE6, 12CS6 or 12SA7GT. 5 inch board. Transmitters Ham Radio Transmitters For Sale. The kit includes terminal strips, solder lugs, tube sockets, wire, newly manufactured variable capacitor, resistors and tested NOS or This little gem has a maximum input of 10-12 watts so will typically produce around 4 or five watts of output – a vacuum tube QRP transmitter! If you have worked mine (which is set up for 4-watts out), you know how nice it sounds and you may be tempted to build one. Click on the Volume Number or cover image to display the full issue in PDF format. Nominal output power 200 Watts. Now your antique radio can play some of the same programs it did when it was new! With your cassette tape player, phonograph or high output microphone, this one tube transmitter becomes a miniature AM broadcasting station, patterned after the 1939 Zenith model S-7000 Wireless Record Player. 5. 50 wired/1949-52 Size: 11. Even-harmonics are  25 Oct 2017 It was a transmitter for the novice which put out a very respectable 65 watts on 80 and 40 meters. 397 S. The antenna coil was salvaged from the oscillator circuit in a typical old radio with a 455kHz I. It goes anywhere, works like a horse and is driven by very low level exciter. This particular circuit keys quite well. 8GHz FM-Analog Outdoor 960H Transmitter & Receiver System - Range 2,000' - TCO-5808R6 $875. FM, AM, Tube, Digital, Analog, HD Radio… available for your radio to broadcast at its best! The heart of the Li'l 7 transmitter is the 117L7/M7 GT tube. With Econco and Richardson (a division of Econco)  These tubes were sometimes referred to as “pencil” tubes because of their small stature. The basic transmitter is listed in the 1940/5th edition of the Stancor Hamanual as the Stancor 10P. Original Schematic as delivered. Vacuum Tubes and Radio Tubes Our specialty. The overriding consideration is to meet the  Is the final power tube of the transmitter capable of delivering power in excess of the desired operating level? Or is the demand for performance so great that  By 1914 the essentials of tube-based transmitters had been worked out. for a very high performance level outdoors and up to 70 ft. This is the classic InfOspot Talking House AM Radio Transmitter System, the most popular license-free radio transmitter system of its kind ever manufactured. $22. Two Tube Transmitter! Now it's crystal controlled. Sets the desired 20 mA point – must set the tube size first. To learn how I restored many vintage radios and tube televisions, also visit our Restoration area. Xtal oscillator - 6AG7. This marvel of engineering is at the same time an oscillator, mixer, and amplifier -- all in one valve structure. Weight The transmitter tube in the pictures is a 6L6G, but it will also work with a 6V6. UPC/EAN: 609722133142 Traveling Wave Tube. 5 kW to 40 kW VS Series Feature-rich rack-mount, HD Radio-ready transmitters: 300 W, 300 W LPFM, 1 kW, and 2. This fuse may be a strand of copper wire or a pig tail fuse. Johnson Transmitters; Johnson Viking I Modes: AM/CW Bands: 160 - 10 Meters bandswitching Output Power: 100W-AM, 115W-CW VFO: External (model 240-122) Power Supply: Internal Final Tube(s): 4D32 Modulator Tubes: 2 ea. Low Range Differential Pressure Transmitter combine low ranges with stability and reliability. Our second feature is a miniature AM broadcasting station, patterned after the 1939 Zenith model S-7000 Wireless Record Player (long gone listing, now an ebay search for zenith tube am transmitters) Next a quite successful 6888-based AM transmitter. 5 kW Delivers long-range Bluetooth signal that other transmitters have difficulty matching. The Mosquito transmitter is ready built and ready to run, featuring a crystal controlled frequency synthesizer for accurate tuning with up to 110% modulation. Many hams fondly remember their first homebrew transmitter--it is hard to forget the warm glow of a vacuum tube  The AA8V/W9EXI 6CL6 One-Tube Transmitter - Schematic Diagrams and Circuit Descriptions. Transmitter Filament Fuse Most Drake transmitters and transceivers have a fuse in the filament power. plate voltage of the tube by CW 6L6 Vacuum Tube Transmitter Thoery The 6L6 Transmitter I am to build is that of CW (Continuous Wave) type. Three Tube Transmitter! Has a selectable preamp, solid state or tube. 21 Oct 2019 Fully integrated microwave tube; High voltage switched mode power supply; Built in test electronics (BITE); Designed for the harshest  Steve sent me these pictures of his Phasitron transmitter restoration workshop back Here's the Phasitron tube (with the mu-metal cover removed) in its natural   I'd only built one tube transmitter before, but it was from a Handbook circuit. It is a very tough tube that is not heavily loaded in the Viking. Some references may list one or the other, or use the number 117L7/M7. New tubes can be   No any adjustment of output tubes standing current is necessary. F. Google. My original One-Tube Transmitter was built using a 6M11 tube which I just happened to have on hand. In other applications, differential-pressure transmitters using diaphragm seals can  80 Meter Tube Transmitter. Socket is very rare. If you step through each page carefully, you'll come to see my own learning  Designers of phased arrays consider many array aspects before they accept a SSD/vacuum tube into a phased array. Only certain VR tubes were made with radioactive stuff in them. My first experiences with self-built radio stations I collected in the upper shortwave range. That was, after all, a common construction technique for simple, beginner's tube transmitters. The operation of the 6CL6 transmitter is actually quite sophisticated, despite the simple appearance of the circuit. The reflex klystron (also known as a Sutton tube after one of its inventors, Robert Sutton) was a low power klystron tube with a single cavity, which functioned as an oscillator. Even today, the German verb "funken", literally, "to spark", also means "to send a radio message/signal". When it comes to radio transmission, BE’s transmitters are hard to beat. Note:  28 Sep 2016 VT-218 JAN-100TH vacuum tube transmitter manufactured by Industrial and Commercial Electronics (ICE), Belmont, California for  7 Mar 2015 This transmitter uses a 6C4 tube and can transmit a powerful 4 W signal. Pictorial diagram of a simple spark-gap transmitter showing examples of the early electronic components used. 3V for the tube filaments. You'll also  Introduction: Bring back the nostalgia with this one tube transmitter. I ended up building another transmitter. frequency. I also decided that this new transmitter would use carrier control, as did the  Welcome to Station QRP! Bring back the nostalgia and build your own low power AM tube shortwave transmitter! Circuit diagrams from simple to complex. Sivan, 9780412579509, available at Book Depository with free delivery worldwide. Parts substitution skills will be important but it's likely every part needed is still available. The heart of the circuit is the electron-coupled crystal oscillator shown above. And they exhibit certain advantages over single-tube or parallel configurations of two tubes. The EL84 tube is still available or can be salvaged from an old radio set. A KC5LDO 6L6 Transmitter, W5DXS - Heart Of Texas DX Society Amatuer Radio This circuit also works well with the 6V6 tubes, although output will be less. The design of the transmitter involves the type of circuit, the choice of component values, and the choice of the particular tube used. The stability, precision, and software flexibility of DDS VFOs make these devices   On this page I will detail my efforts to build a high quality tube-type AM transmitter . The power supply is using a 5Y3G tube. Older tube transmitters may not have spare parts. The sense tube is installed in the tank and connected to the pressure transmitter and the air supply through the flow restrictor as shown in Figure. 2709 Fax: 303. It is the only such system certified under FCC Part 15. I wanted to do a QRP transmitter of my own design, more or less, and this is the  Fred offers three more tube transmitter projects offering both crystal controlled and VCO tube-based transmitters for any and all possible uses. In fact, it's fairly "cookbook", using a pentode-based colpitts crystal oscillator, followed by a beam-power-pentode final amplifier with pi-output network, all cathode-keyed. Jan 29, 2016 · 75 years ago this month, the January 1941 issue of QST contained the plans for two one-tube transmitters, both using the recently introduced 117L7GT tube. This is a variation of the triode/pentode family of glowbug transmitters. It was used as a local oscillator in some radar receivers and a modulator in microwave transmitters the 1950s and 1960s, but is now obsolete, replaced by semiconductor Jul 01, 2018 · The Mosquito 1 Watt AM Transmitter dsigned for the new Low Power AM standards being introduced in Scandinavia and the Netherlands, including laagvermogen AM. It features a Pierce   24 Jul 2015 I remember writing a few years about the efficiency advantages of multi-stage depressed-collector IOT tubes used in digital transmitters. It uses a 6L6 with a 6X5 rectifier and a 0D3 voltage regulator tube on the screen. tube, was applied in commercial ham transmitters in the early 1960’s including the Gonset G76, Hammarlund HX-50, Hallicrafters HT-40 and HT-44, and the early Swan transceivers. The triode acts as a Pierce crystal oscillator, and the pentode as a conventional power amp. Make Offer - (1) Vintage GE VT-4-C Tube 211 General Electric Ham Radio Transmitting Tube E2V IOT 8303r from Axcerra visionary uhf ch 48 tv transmitter $708. Many amateur amplifier designs around this beauty. It was an updated version of the author's “Hart  Microwave Tube Transmitters by L. Under- drive kills transistors and tubes. I have those manuals going back to 1950 and the older projects are much more interesting to me. A 6AB4 or 6C4 is used as an audio preamp and the 6888 as the transmitting tube. 5% FS Accuracy, Ranges from 0 to 25" w. One Tube Transmitter! Based on the Antique Electronic Supplies kit. tube transmitter 1 Articles . 807 p-p New Price/Year: $209. The power output is only about 5 watts. KnightKit Transmitters Enthusiasts; C-QUAM AM Stereo Transmitters: Inovonics Wireless Corporation. Here is my new 6L6 AM and CW station. Although any high-power FM transmitters use transistors, the best and cheapest way to get a high power output in the FM band is via the use of a tube. My number one priority was adding "spot" capability. indoors. AM tube transmitters are rugged but less efficient that solid state counterparts. The signal can be tuned in the frequency range between 88 and 108  7 Jan 2015 Tube Transmitters. The transmitter also uses push-pull 807 tubes for Use of the spark-gap transmitter led to many radio operators being nicknamed "Sparks" long after spark transmitters ceased to be used. a. 1) The classic Hartley single-tube transmitter. Building Projects. My first transmitters were using a 6AQ5 and then A 6V6, 6F6 or 6L6 beam power tetrode tubes (usually used in audio power amps) as xtal oscillators coupled to the antenna with a variable link winding on the plate tank coil. It does not convey the spoken word using AM (Amplitude) or FM (Frequency) modulation. Output power is around one watt with the VFO version of the circuit, the crystal version may produce less power if the crystal is not late 1940's design code (CW) 'home brew' transmitter. The Power Supply for the 40-30 transmitter is a modified version of the "Economy Power Supply" featured in the ARRL handbooks. Automatic bias circuit adjust current through mighty QB5/1750 tube. It can go almost twice that by pulling out the 0D3, but the keying is not as good that way. Thanks to Jan SM5GNN. 25% or ±0. Works extremely well as an entertainment hub. Home-Brew Tube. tube transmitters