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Drake R7 shortwave am ssb cw receiver collectors cond
During the history of manufacture of hobbyist radios and receivers, some of the units have defined the niche and cut a piece of the pie of notable and outstanding equipment pieces within that history. The C*ollins R*390A did this with the military receiver with it's mechanical filters coupled with great sensitivity and other performance features. The S*ony ICF*2010 did this with a high performance portable at an affordable price and an outstanding synchronous detector. This Drake R7 belongs in this list as one of the first high performance general coverage receivers built with the hobbyist in mind and offering an array of receiving features that delivered a receiver that was, and still is, considered to be one of the best receivers made. I will endeavor to review what makes the R7 an outstanding unit below, but first will give some specifics regarding this particular unit found in the blue text.
This R7 comes with a good copy of the user manual in a 3 ring binder. In addition, I will be including a CD with the user manual, service manual, advertising literature, catalog listings and the data sheet. This CD is supplied for convenience, education, and for servicing should that ever become necessary.
Cosmetically, this R7 is nearly perfect. The front panel is clean and looks outstanding as do most of the rest of the unit. I did see a slightly darker area in the shape of a square that is on the top cover near the front. Upon casual inspection, one could overlook this. But once you know it is there and look for it, the darkened area becomes more obvious. Internally, the receiver is also beautiful and appears to have been used sparingly. The original power cord looks to be virtually unused. Based on the appearance of this receiver both externally and internally, I believe it falls into collector's quality status. The top cover could be replaced, if desired, given some time as the cover is also shared with the Drake TR*7 transceiver and thus not rare to come across.
This R7 receiver was manufactured by Drake from 1978 to 1981 and I suspect this was done in reasonably limited quantities due to the selling price of about $1500 without options. The comparable price in today's dollars would be over $4,500. I checked, and Fred Osterman in his book "Shortwave Receivers Past and Present" also lists this as a scarce unit. This R7 has a couple of extra filters installed giving it the IF bandwidths of 6 , 2.3 and .5 khz.
The R7 was the standard version receiver produced by Drake from 1978 to 1981. Due to the choice of installed filters, this R7 has not only the standard IF filter of 2.3 khz sideband, but also the 500 hz filter for CW and the 6 khz filter for AM listening. Thus the listener can utilize this R7 for each of the modes of operation. And while the 6 khz filter would be standard for AM listening, the user can also slightly off tune in frequency to use the 2.3 filter in AM or direct tune and listen to the AM signal using sideband.
These filters are the highly regarded 8 pole crystal IF filters that offer great audio.
The R7 has been fully tested and all the controls and functions operate as Drake originally designed them to do. The controls move easily and click into position with authority without the customary feeling that the controls need to be lubed and cleaned. I tested for noise from dirty contacts and heard none. Reception is quite good and the unit is sensitive across the entire spectrum of it's receiving range.
This receiver covers from 10 khz on up to 30 mhz without any gaps in coverage. It has a very strong following among longwave, broadcast band, and tropical band dxer's that have discovered this receivers low noise floor and great sensitivity in these frequencies. Yes, it works well along through the full spectrum of frequencies, but it is especially strong on the lower ones and has earned a reputation that is seconded by Fred Osterman in his book Shortwave Receivers Past and Present as "an excellent receiver for tropical band DXing and also superb on longwave".
Not only does the R7 look nice, but the user is confronted with an array of operating features including:
* Choice of 3 bandwidths 6.0 / 2.3 / .5 /
* Calibrator every 25 khz to precisely determine frequency
* Digital readout down to 100 hertz
* AGC of fast / med / slow / manual
* Multiple antenna inputs (6 position)
* Record and speaker output jacks
* Operates on AC voltage of 100 / 120 / 200 / 240 or 11- 16 VDC
The receiver is a triple superhet with outstanding sensitivity on SSB of .2 uV from 1.8 to 30 mhz.
Let me mention a couple of other unique features found on the R7. First of all, you can connect up to 3 antennas and a second receiver to the back panel. This is helpful as the R7 has a control that acts like an antenna switch and allows the user to choose between antennas, but also to share the antenna inputs with a second receiver. This also offers another neat feature for the BCB dxer. By connecting one antenna to the "main" antenna input and a second antenna to the one marked "ext rcvr" and by setting the selector switch to the Main/Main position, the antenna splitter works as a combiner. Thus, the user can use two phased longwires or combine a longwire with a loop antenna for some interesting results.
Secondly, there is a rear panel connector on the R7 for an input that allows the digital readout to act as an outboard 150 Mhz frequency counter. Those with some electronic expertise can take an insulated wire and wrap it around the oscillator coils of the tube receiver so that it acts as an inductive pickup loop. Then the pickup is fed by coaxial cable to the rear RCA input jack and by activating with the front panel switch, the digital display will show the operating frequency of the tube receiver incremented by it's IF.
The R7 is a modular receiver which owes to the excellent Drake design and circuitry layout. This helps to streamline diagnostics and repair and gives the circuitry a clean layout as seen in these pictures:
I love looking at vintage receivers and placing them within historical perspective. In this case, I was able to locate an extensive review of the R7 in a 1980 copy of the WRTH (World Radio and Television Handbook). This review was for the R7 based on it's competition and what was formerly available to the hobbyist at that time. Here are some excerpts from this review. While the review was for the stock R7, the enhancements would add further interest, operational flexibility and desireability (with the full compliment of filters) so you may want to consider this when reading the review posted below. Please note that the WRTH catered to the shortwave and medium wave hobbyist so the comments reflect that perspective more than those for amateur radio use:
Unsurpassed shortwave and mediumwave performance
Very selective (using combination of filters, passband tuning, and RIT tuning)
Excellent ECSS reception (exalted carrier selectable sideband for AM signal listening to prevent distortion and eliminate sidechannel interference)
Exceptionally accurate digital frequency readout
Capable of producing unusually good audio
Flexible antenna inputs / controls
Built in preamplifier for shortwave reception
Unsurpassed receiver for serious SW / MW DXing, SW / MW broadcast monitoring, and technically-oriented SW / MW superior fidelity listening.
The Drake R7, like a worthy sportscar, is a joy and a challenge to operate - provided one knows how. It's front panel is festooned with no less than twenty-five knobs and buttons, each of which gives the operator an additional measure of control over the receiver's functioning. When properly used, the R7 is capable of equaling, and sometimes bettering, any receiver we have tested to date for use in receiving medium wave and shortwave signals.
The R7's extreme flexibility, combined with outstanding performance characteristics in each function, combine to make possible reception of signals heretofore inaudible, and to make more usable signals formerly audible. For detection of AM signals, a synchro-phase detector is used not only to reduce distortion over what would be encountered with a standard diode detector, but also to allow the use of limited selectable sideband detection without having to resort to local carrier injection. Additionally, a continuously variable passband control is incorporated to allow reception not merely of one sideband over another, but also of any of the chosen portion of that sideband." (conclusion of WRTH info)
The R7 was truly an outstanding receiver in it's day with performance features that were standard equipment that even some recently manufactured receivers do not have....like dual antenna inputs, passband, RIT tuning, notch, pre-amp, noise blanker, etc. When compared to some of the higher end receivers manufactured in the last 10 years, it may seem less remarkable, but this was the Cadillac in it's day and performance about 30 years later is still phenomenal.
The R7 has an arsenal of weaponry to help clarify that signal, and as mentioned in the WRTH info above, can be used in combination to grab and "hear" that signal. Truly, this receiver is one of RL Drake's finest offerings to the listening hobbyist. I could literally write volumes more about this receiver based on my own experience and what could be gleaned from the WRTH review, but you at least have a good idea about the performance and features that this unit offers. For some futher study and reading, here are some sites for you to look at.
If you would like to read some of the nice comments of this receiver, you can visit eham here where the 5 reviews all give the R7 / R7A a full 5 point rating!
http://www.eham.net/reviews/detail/862
Here is the DXing.com info on the R7 and the R7A where you will see it is given the highest rating of 5 H's:
http:// /rx/r7.htm
And here is some interesting info found on another site:
http://www.zerobeat.net/drakelist/drakemod/drmod14.html
I would like to add that the R7 is a delight to operate. If you like receivers that do everything for you and offer direct keypad tuning, you should look elsewhere. However, if you like the "feel" of an analog tuner and the idea that you can control precisely a number of operational features, you will love this receiver. As a hands-on receiver, it offers hours of tuning fun.
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