I soldered up the existing wiring to the two tabs on the lamp replacement as the final step in the process. The complete manual for the l4b is available free for download from bama boatanchor manual archive. It covers 80, 40, 20, 15 and 10 meters 10 meters not available on late production. This link is listed in our web site directory since monday nov 18 20, and till today drake r4b manual has been followed for a total of 341 times. For ibm compatibles there are a number of packages available. In this video we take a quick look at the drake l4b with solid state relay failure. First try to have your r4b at its original specifications.
This unit is mounted inside the amplifier and transforms the 2427vdc key closure to approximately 1 vdc at 1. The drake team has been hard at work throughout 20 to help ensure that your firm has a successful, rewarding filing season in 2014. The hv ps may need refurbished due to age of filter caps. Whats everyone think about this transformer for building an upgraded power supply for my drake l4b. While using my drake l 4b amp the other night i detected an electrical burning odor coming out of the power supply. Qsk for the drake l4b amplifier drake radio repair. Jan 17, 2012 in drake amps ive owned l 4 l 4b used the same resistor, its actually in the power supply ive just replaced it with a piece of wire and added a real glitch resistor of higher value. The l4b has been designed incorporating several interlocks to prevent danger ous electrical shock 0 however, it is possible to disconnect the high voltage ter minal while the l4b is turned on, this is a potentially dangerous situation and should never be attempted for any rea sono when disassembling the l4b, the high. Is there any computer software available for my drake receiver.
Drake software users manual about your drake software users manual tax year 20 5 1 introduction thank you for choosing drake software. View and download drake l75 operators manual online. My last l4b was upgraded with a sb220 peter dahl plate transformer with the sb220 cap bank and diode board. Drake l4b hf amplifier wb4hfn web page schematic diagram. Drake r8, r8a, r8b, r8e communications receiver email mailing. Highest quality drake r4b operating manual on 32 lb w11x17 schematic.
The drake l4b is one of the highest quality amateur amplifiers ever made. Drake software is a complete professional tax preparation program for federal and state returns, business and individual. About drake r4b manual the resource is currently listed in in a single category. Drake l4b revised schematic to include the relay i also replaced.
It was big, bulky, noisy, and very s l ow, but it could handle a decent amount of power, even with slightly higher swr. Amp was idling at the time and just before i shut it down the plate voltage meter was moving back and forth from about to 2500 volts. Does anyone have at least the power supply portion of the schematic they can send a jpeg, pdf or provide a link. The one weak link in the design is the combined ac power and ssbcw tune rocker switch. Oscillator, final amplifier, speech amplifierdriver, modulator, rectifier.
Drake l4b owners manual and service instructions service. Harbach electronics, llc your worldwide source for amateur. Note that there is a limit to the number of files you can download. Exciter rf is fed to the input circuit and then to the filamentcathode via the large brown mica capacitor. Schematics for l4b amplifier and power supply last 2 fold out pages general specifications frequency coverage ham bands 80 through 10 meters. This included the l4b amplifier section and the l4ps high voltage power supply. The drake l 4b amplifier is a dual 3500z amplifier that covers the basic 80 through 10 meter bands without specific warc band 60, 30, 17, and 12 meters coverage.
The selected page will appear in this section of the screen. Imo the problem with the drake design is that if the. Visit us online for more information or to download service manuals today. In this page you find schematic, users and instructions manuals, service manuals, technical supplement, leaf leads and other good stuff. Power requirements are 115 vac 5060 hz 30 amps or 230 vac 5060 hz 15 amps. I have had several amplifiers since, including an alpha 76pa, that i have now, and i cant sell this l 4b. Drake 2b2 receiver sch service manual download, schematics. The 12 volt regulated power supply is an incredibly bad design. The first table i got to had a drake l 4b displayed and for sale. Get the best deals on drake l4b when you shop the largest online selection at. Drake l4b 8877, drake, tr4, tr7, drake radio, drake receiver, drake. All manuals include schematics unless otherwise noted.
I use it primarily on 80, 40 and 20 meter ssb, but it performs well on am. I have been unsuccessful in finding a usable reader. View online or download drake r 4b instruction manual. It is a real workhorse design that can stand modifications to improve performance and stability. Drake r4b sw 1,530mhz receiver sm service manual download. Drake l4b from 1978 or new ameritron 80b worldwidedx. These packages offer different features for different applications. Below is a picture of my vintage drake 4b series hf station. Note that the ssbcw wiring is unchanged from the above drawing, but that the. Without it you run the risk of severely damaging the keying circuit in your transceiver.
The high efficiency class b grounded grid circuit uses the new eimac 3500z zero bias triodes. The r l drake model l4b linear amplifier offers continuous 2000 watts pep ssb, and watt dc, c w, am and rtty operation covering the ham bands 80. This allinone board provides a softstart, softkey and user adjustable biasing for the drake l 4b amplifier. Only the drake r8, r8a, r8b and r8e european model of the r8a had computer support. The main category is drake r 4b reciever that is about drake r4b receiver. View and download drake 2b instruction book online. Resist any temptation to just run these in with the nut driver. Sk401 softkey keying interface harbach electronics, llc. Service manuals, schematics, eproms for electrical technicians. Free shipping on many items browse your favorite brands. More drake power amplifiers drake l4b l 4 b l4b service manual and specs drake l7 l 7 l7 service manual and. The drake ac4 power supply was used to power a number of transmitters and transceivers in the drake 4 line. Equipment manual section select pages by clicking on the individual page number or manual section from the menu on the left.
Drake l4b amplifier solid state relay modification w8zr. The drake is wired to 240 volts and i dont have a schematic diagram of the supply. If you are a new customer, your efile password was included in the email confirming your purchase. Second, put a 100 nf capacitor in parallel to r19, cathode resistor of v4, this will increase the gain and the effectiveness of the avc.
The drake l 4b has watts pep power input on am, cw and rtty and 2000 watts input on ssb. High resolution scans of original manual for the tr4c, plus addenda for cw and cwrit versions. You always know what your software will cost, which just happens to be one of the best deals in the industry. Drake l 4b amplifier solid state relay modification the drake l 4b is one of the highest quality amateur amplifiers ever made, a timetested design, ruggedly constructed, with top notch components. Drake ultimate ham radio operation repair service manuals.
The drake l4b amplifier was designed and built in the middle 1960s as a two piece unit. I am now accepting new manuals for inclusion in this archive. I looked down into the top of the perf top cover and just fell in love. If you have some stuff that not is listed here you can donate this by contact mods. Buy drake drake software professional tax software. The amplifier was a very rugged amplifier and designed as a two final tube amplifier using the 3500 or similar tube. Drake l4b power supply harbach electronics kit installation.
The openframe relay has been used in amplifiers dating back to the days of the drake l4b, henry amps, and heathkit amps. These manuals are available for download and free of charge. I put out queries on the various amp reflectors and still. I began contemplating a second and later third drake l4b redesign powered by a newly purchased.
I had not seen any pictures of the ac4 i obtained prior to purchasing it. Harbach electronics is proud to announce the new es4l4b softstartsoftkeybias board from electronic specialties. This module was specifically designed for an easy retrofit into the drake l4 or l4b amplifier. Many modern amplifiers now use much smaller plasticenclosed relays. I figured, it is just a power supply, how much can go wrong. Select pages by clicking on the individual page number or manual section from the menu on the left. This module was specifically designed for an easy retrofit into the drake l4 or l 4b amplifier.