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Hallicrafters Items

 

Production Year 1940 at $74.50

The Hallicrafters S-22R is a Single Conversion, Superheterodyne, general coverage receiver that is used for the reception of AM and CW signals. The Hallicrafters company dubbed this receiver the "Skyrider Marine". Besides listing the frequencies, the analog frequency display has been calibrated at the bottom of the dial from 0 to 100. The main tuning dial of the S-22R is gear driven and makes use of flywheel tuning which gives a solid feel to the operation of the receiver. The S-22R contains 8 tubes in its circuit and has four bands covering 110 KHz to 18 MHz. The first band covers 110 KHz to 410 KHz, the second band covers from 400 KHz to 1.5 MHz, the third band covers from 1.7 MHz to 5.9 MHz, and the fourth band covers from 5.3 MHz all the way up to 18 MHz. The Intermediate Frequency(IF) of this receiver is 1600 KHz. The five inch loudspeaker is mounted behind the front panel and faces out towards the front of the unit. It is of the permanent magnet moving coil design. Received signals exit through a perforated screen on the front of the unit.

The front panel controls consume the entire bottom edge of the face of this receiver. Starting at the left is the Radio Frequency(RF) gain control knob which is used to adjust the sensitivity of the receiver. Next is a 4 position Band selector knob that is used to select one of the four bands for reception. Next we run into a control labeled Audio gain which is simply another name for Volume control. At this point we run into the first of the three front panel switches. This first switch on the left is used to turn On and Off the Automatic Volume Control(AVC). This switch in most cases is preferably on when the operator is receiving phone or AM signals. With the switch in the off position, the operator should control the sensitivity of the receiver with the RF gain control, otherwise the receiver will block or overload on strong stations. The switch to the right of the AVC is used to turn On and Off the Beat Frequency Oscillator(BFO). This switch would normally be turned on to receive SSB and CW signals. Directly above these two switches in the center of the front panel is the Main tuning dial. The next control knob that we run into has two functions. This control is used to turn On or Off the Power to the receiver and its second function is used to adjust the Tone of the received audio signal. The last knob that we come to is the Pitch control which allows the operator to change the pitch of the received CW signal. At the right we have the last of the three front panel switches which is labeled as the Send/Receive switch. This switch is used when the S-22R is paired up with a transmitter. The Send/Receive switch removes the plate voltage from the tubes of the S-22R which makes the receiver inoperative during times of transmission. This switch can also be used to conserve power during a stand-by period when it would be important to have the radio spring to life with just a flick of a switch instead of having to wait for the tubes to warm up. Lastly at the bottom right hand corner of the front panel is a 1/4 inch headphone jack. Inasmuch as no direct current flows in the headphone circuit, crystal type headphones can be used in this jack. When headphones are plugged into the headphone jack, the speaker is automatically disconnected.

The 8 tubes that are used in this receiver along with their functions are as follows, 6SK7 = RF Amplifier, 6K8 = Converter and HF Oscillator, 6SK7 = 1st IF Amplifier, 6SK7 = 2nd IF Amplifier, 6SQ7 = Detector and AF Amplifier, 6J5 = Beat Frequency Oscillator(BFO), 25L6 = AF power amplifier, 25Z5 = Rectifier. The radio employs a standard #47 bulb for the dial lamp and is housed in a sturdy metal cabinet.  The power source requirements are 110 to 125 volts using either AC or DC at 60 cycles. At 117 volts the receiver consumes 50 watts. The Hallicrafters company also manufactured a 220 Volt DC version that used a special type of line cord with a dropping resistor. The physical dimensions of the radio are 18 1/2 inches wide by 8 1/2 inches high by 9 1/4 inches deep.

The photograph on the right is of the back of the receiver. The connections and such found here are as follows, from left to right, AC/DC power cord, in the center is a cut out that gives access to the serial number and at the right is a 3 terminal antenna strip. The 3 terminal antenna strip is marked "A1", "A2" and "G" and known as Antenna 1, Antenna 2 and Ground. A jumper bar consisting of a strand of wire is normally connected between terminals "A2" and "G" for single wire antenna systems as well as unbalanced antenna transmissions lines. For a doublet antenna system with a balanced transmission line, the jumper between "A2" and "G" would be disconnected. If a concentric transmission line(coaxial cable) with a grounded outer conductor is used, connect the inner conductor to terminal "A1" and the outer conductor to "A2" followed by a jumper wire between terminals "A2" and "G". The station ground connection is to be connected to the "G" terminal.    

The Hallicrafters S-22 receiver is very similar to the S-22R receiver featured on this web page. The frequency range of the S-22 is from 140 KHz to 18.5 MHz. What sets the S-22 apart from the S-22R is the exposed analog frequency display rather then it being behind a transparent window as seen above.

  

*** A special thanks to a friend and fellow collector Howard Davis(G6LXK). While viewing this web page Howard noticed that the Pitch control knob (last knob on the right) was not original to the radio and he sent a replacement from England to the U.S. in order to rectify this problem. This is not only the mark of a true collector and outstanding amateur radio operator, but it is the mark of a wonderful person that I am honored to have as a friend. The pictures have not been updated to show the new knob installed.***  

The photograph on the left is of the top of the S-22R with the hinged cover in the open position. This picture displays the tube compliment and some of the other major components that are found on the top of the chassis.

The photograph on the right is of the bottom of the receiver with the bottom cover removed. This picture was taken halfway through the restoration process and shows many new parts installed. Most noticeable are the orange and yellow capacitors. The old waxed paper and molded paper capacitors are often found to be the main source of trouble in these older receivers. It is usually recommended that all of these capacitors along with the electrolytic capacitors be replaced. The reason being is that over time the old capacitors may start to dry out and become open, shorted or leak which can hurt the performance of the receiver and possibly cause serious damage to some of the major components. Some times when I do these restorations I actually drill out the gunk from inside of the old electrolytic capacitor and stuff the new replacements inside. I normally do this so that the radio would keep its original appearance. Capacitors that are made today are not only sturdier and more precise, but are also much smaller. A capacitor from yesteryear that was the size of a roll of quarters is now the size of a pencil eraser today. In most cases, the new replacement capacitors will easily fit inside the body of the old capacitor. Some folks have been known to take this a step further and go so far as as to even stuff both the waxed paper and molded paper capacitors to give the set a museum quality restoration. Before I solder any wires or leads to the chassis or to the tube pins, I clean the oxidation and other gunk from the connection point with a Dremel tool using a wire brush attachment. The square black object in the upper right hand corner is a choke with the Hallicrafters "marine" protective coating on it.  A factory fuse block is mounted on the under side of the chassis and should contain a 250 volt 2 ampere 3AG type fuse. The bottom cover of the cabinet will need to be removed before access to the fuse is granted.

WARNING!! In the AC/DC receivers such as the one featured on this page, the chassis and cabinet are normally at the same potential. In later years, some manufacturers attempted to isolate the chassis from the cabinet with insulators. It is very important that you do not rely on these insulators a half a century later. A lot could go wrong such as, are they still in good condition, did a previous owner reassemble the radio properly, and so on. Depending on which way the power cord is plugged into the wall can put the entire receiver at 120 volts above ground. This means that if the operator has one body part resting on an earth ground and reaches over and touches an exposed part of the receiver, the operator can receive a potentially fatal shock.

The partial schematic above is for the Hallicrafters S-22R receiver. This schematic would feel right at home with many of the AC/DC receivers, or numerous other electronic items that are built this way. There is no power supply transformer in the circuit of these items which makes them dangerous if the operator becomes careless. Actually, the reason the set can run from a DC power source is because there is no transformer. Today, an item built this way and with a metal cabinet would never get past the Underwriters Laboratory(UL). In fact, if you were to take a survey of the electrical items in your house, what you will most likely find is that just about every appliance with a metal case has a three prong power cord attached to it. As seen in the schematic above, the item will work no matter which way it is plugged into the wall. One way allows the chassis to be connected to the hot wire in the home wiring, while flipping the plug the other way connects the chassis to the neutral side of the house wiring. Either way can be dangerous as both the hot and the neutral house wires in the U.S. carry current. Even though at the fuse panel both the neutral and ground wires go to the same place.

Picture this, the receiver cabinet is hot with 120 volts of AC. You have a hand resting on a desk lamp that uses an older non-polarized power cord or is grounded by a newer 3 prong plug, or your hand is resting on the station ground, or your feet are propped up on the heater, or a thousand other possible ways you could easily be at ground potential, now you reach for a switch on this radio and ZAP, the current runs through your body as it makes its way to ground and kills you. Now your wife becomes a widow and we see your stuff listed at auction under the title "From the estate of a SK". I realize that this sounds harsh, but in most cases there are no second chances. What's that I hear you say? You fully understand the dangers and will watch out for this? What about a family member when you are not home? Do they also understand the danger? Do not risk it. Explain the dangers to them and check the voltage on the chassis with your VOM with the on/off switch in both positions. An isolation transformer can also be used, or better yet, unplug the device when you are away.  

The photograph on the left is of the bottom of the receiver with the bottom cover removed. This picture was taken before any of the restoration process had begun. This Hallicrafters S-22R was just slap full of cobwebs and insect remains. It must have sat on a shelf or up in an attic for many years before it found its way here. The picture on the right is of the inside front right hand corner of the receiver. The big brown thing that the red arrow is pointing at is actually the factory 5 inch speaker.

  

ALIGNMENT PROCEDURE:

In order to do an alignment on this receiver the technician will need four basic service tools. These items include a full wave signal generator which must cover the frequency range of the S-22R including 1.6 MHz, some way to connect a VTVM(Vacuum Tube Volt Meter) or some other output indicating meter to the headphone jack, a non-metallic screw driver and a dummy antenna. The dummy antenna is nothing more than a .0002 MFd capacitor(0.0002 uF, 0.2 nF, 200 pF, 200 MMFd, 200 uuF = same thing) for bands 1 and 2, and a 400 ohm non-inductive resistor for bands 3 and 4.

The first step in the alignment procedure is to turn on the receiver and the signal generator and allow each of them to warn up and stabilized. Around a half an hour will often suffice. The next step is the proper setting of the controls on the front of the receiver. Set each of the controls as follows, tone control at maximum high frequency position, the AVC and BFO is turned off,.RF and AF gain is set at maximum.

There are normally at least two alignments that must be preformed on a receiver. It is important to always do the IF alignment first and the RF alignment last. This receiver is no different and the IF alignment is preformed first. The IF of this receiver is 1600 Kc or 1.6 MHz. This is some what of an odd ball IF as many receivers have an IF of 455 Kc. Why is knowing the IF frequency important? Well, you must know the IF frequency of the receiver before it can be properly aligned.

The next step after we have completed the above is to set the band switch to position 3 and tune the receiver to 5.0 MHz. Tune the signal generator to 1.6 MHz. Now connect the hot side of the signal generator to 6K8 grid cap through .01 MFd capacitor and place the ground of the signal generator to the chassis. Using the non-metallic screw driver, simply adjust screws S1 through S6 that are found on IF transformers T1, T2, and T3 for maximum gain. These transformers are located on the top of the chassis and all six screw heads point towards the rear of the receiver. That's it, you are done!! That is all there is to doing the alignment of the IF section on this receiver. 

WAIT, don't change the settings on that signal generator just yet. While it is still set to deliver a signal on 1.6 MHz we might as well check the BFO adjustment. With the 1.6 MHz signal being fed into the IF amplifier of the receiver, turn on the BFO switch and place the Pitch Control knob with the white dot strait up. Now adjust screw S7 that is located on the top of transformer T5 for a zero beat. Transformer T5 is located on the top of the chassis. That's it, you are all done with this adjustment. Now the Pitch control is centered and you will be able to vary the frequency of the beat note to your complete satisfaction.

The RF alignment is just as easy but a touch more tedious. It involves changing the frequency of the receiver for each band and matching this frequency with the signal generator. There will be a total of eight frequency changes that will need to be made, two for each band. One thing to keep in mind is that it is some times helpful to run through each band a second time for a final tweaking which will yield superior receiver performance before moving on to the next band.

Lets begin, set the receiver controls as stated above and switch the receiver to band 1. Next, tune the receiver and signal generator to 125 Kc. Connect the hot lead of the signal generator to antenna connection A1 using a .002 MFd capacitor and place the ground of the signal generator on the chassis. A jumper between antenna connection A2 and G should be installed.

Now adjust P1 which is located under the chassis for the strongest signal on the VOM. While the receiver is still on band one, it is time to align the other side of the dial. Tune both the receiver and the signal generator to 350 Kc and adjust capacitors CC, CA and CB, which are located underneath the chassis for the strongest signal on the VOM.

For band 2 we need to tune both the receiver and the generator to 450 Kc and adjust P2, which is located on the top left side of the chassis for the strongest signal on the VOM. As before it is now time to adjust the other side of the dial on band 2. Tune the receiver and generator to 1.4 MHz and adjust capacitors CF, CE and CD which are located underneath the chassis for the strongest signal.

It is now time to remove the capacitor that is connected to antenna terminal 1 and replace it with a 400 ohm resistor. Put the receiver on band 3 and tune it and the generator to 2.0 MHz. Now adjust P3 which is located on the top of the chassis for the strongest signal on the VOM. Next we need to tune the receiver and generator to 4.5 MHz and adjust capacitors CJ, CG and CH, which are located underneath the chassis for the strongest signal on the VOM.

Hang in there as we are now on the home stretch and are just about done. The next to the last step begins by switching the receiver to band 4 and adjusting it and the generator to 7 MHz. With this done, we now need to adjust P4 which is located on the top left side of the chassis for the strongest signal on the VOM. The last step in our RF alignment is to tune the receiver and generator to 15 MHz and adjust capacitors CM, CL and CK, which are located underneath the chassis for the strongest signal on the VOM.

All of the adjustments above will need to be done with the non-metallic screw driver. For safety reasons, do not preform this work alone or if you are tired. It is not worth your life.

  

  

Resources:

Radios by Hallicrafters with Price Guide by Chuck Dachis

Hallicrafters owners manual

Sam's photofacts by Howard W. Sams & Co., Inc.  

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