MRHS Merchandise

The photo of the MRHS T shirt in Newsletter No. 18 brought quite a response!  Many writers wanted to know if they could buy the T shirt even if they would not be at Pacificon.  Others demanded other MRHS merchandise such as mugs!

To be honest, we were a little overwhelmed by this unexpected response.

Here at the MRHS we just don't have the facilities to set up a merchandise operation, involving as it does keeping track of the orders, making sure everyone gets what they ordered, replacing lost items and keeping on the right side of the tax man.

However... we are looking into the possibility of setting up an on-line merchandise store with all the details handled by an outside company.  No promises at this point since we're just in the investigation stage.  But we wanted to let you know that we heard the requests for MRHS merchandise loud and clear.

Remote Control by Tone Set - A History

By William F. Ruck, MRHS Maintenance 

Part III of a three part series...

The first part of this series explained why communications is best with separate transmitter and receiver locations and how the transmitters could be remotely controlled. The second part went into detail on the narrow frequency shift tone sets used by KPH and now KSM. This final part explains how the six operating positions in Point Reyes are connected to the tone sets.

Before we get into wiring we need to take a look at the operations side. The maritime radio business had a traffic load that changed from hour to hour and from day to day. The frequencies used also changed from day to night and back.

There was definite skill and some luck in assigning the appropriate number of operators to each shift. Too many operators on duty and they didn't have enough traffic to keep them busy, which meant that company resources weren't spent efficiently. Too few operators on duty and they couldn't process all of the messages which meant that some of the potential messages went to the competition and revenue was lost.

In any event, there needed to be a lot of flexibility in the operations at KPH.

We know from historical pictures that the operating positions evolved over time. We can also tell from those pictures that at least by the time that the receiving station moved to Point Reyes after WWII that there was some method of selecting different transmitters.

The first post war KPH operating room had two positions and was located in the former lunch room of the point to point receive station at Point Reyes, known as RS on the telegraph and teletype lines.   

One of two post war operating positions at KPH located in the point-to-point receive building at Point Reyes.  Note the paper loop for the wheel to the operator's right and other loops hanging on the front of the table.

When the point to point receivers on the second floow were converted from DC to AC operation the battery and motor generator rooms below were made available to KPH.  This is the same location KSM uses today.    

This early photo of the KPH operating after it moved to the rear of the Point Reyes building shows the elaborate paper tape keying system known to operators around the world as "the dotter".  We have the keyer but not the pulley system.  The transmitter selection panel may be seen to the operator's left.

When KPH moved into the rear of the first floor six operating positions were established. Over time those positions were changed and improved to what we are today using for KSM. Different equipment and different desks were used but each time there was some form of switch panel to allow the operator to select which transmitter he (or she) needed for communications with a ship.

To be honest, the first time that I was asked to trouble-shoot a keying problem I was both lost and scared. One issue was that some of the multi-pin connectors were never latched so when I touched anything all of the transmitters would stop keying. This did not improve the temperament of the Operations Department in any way! But once I found a few historical sketches in the files and was able to translate them into the reality that exists I found the keying system to be relatively straightforward.

Further complicating the keying situation is that left behind was transmitter keying selection systems for both KPH and WCC.  WCC on Cape Cod was keyed remotely from KPH in the last several years of operation. Today we use little of the WCC system because it is hard wired to relatively modern tone sets that used to feed a DS1 circuit to WCC. We don't have the other end of that circuit so that equipment basically goes nowhere.

This article will explain in detail how the KPH system works at Point Reyes (RS).

All six positions can select one or more of ten High Frequency transmitters to manually key. Positions 1 and 2 can also key the MF (500 / 426 kc/s) transmitter and select the MF transmit frequency (500 or 426 kc/s, known as the "ZAL" switch). Position 1 can also select one of two sources of continuous Morse streams.  The first is generically known as "The Wheel", the second is for weather and press broadcasts.  One is identified in the drawings as "TFC" and the other is "CQ". Note that tradition had the most senior operator on duty at Position 1.

The term "Wheel" comes from older mechanical methods of storing Morse code.  The original storage method was an actual notched wheel (the remains of one of these still exists at WLO).  Later, two-level paper tape was punched on a Kleinschmidt perforator and then read on a keying head.  We use a Boehme at KSM today but earlier keying heads were made by Creed.  There was also a home brew keyer based on a military unit that we still have in storage.  Once the paper tape was punched the ends were glued together to make an endless loop. Round loop = "The Wheel". This loop then ran in the reader providing either the hourly traffic loop ("TFC") or the station marker "CQ".

The "CQ Wheel" now is:

V V V   V V V   V V V   CQ DE KSM KSM KSM QSX 500/4/6/8/12/16/22 OBS? AMVER? QRU? ANS 500/HF CH3 AR K

The CQ Wheel was a marker that allowed a ship to tune in KPH (now KSM) and choose which band to contact the station based on the best signal received by the ship.

When a ship called the operator would switch from the "CQ Wheel" to manual keying, return the call to the ship, and pass the traffic.

After that if no other ship called the operator would switch back to the "CQ Wheel".

Because KPH in the past and now KSM is licensed on specific transmitter frequencies we always transmit on the same fixed frequency in each band. None of the HF transmitters change frequency. All the operator at RS can do is select which transmitter to key to select an HF band.

A greatly simplified diagram will help explain how it works. There are ten of these circuits at all positions for the HF transmitters.

 

At Position 1 the operator could select either TFC or CQ or nothing with the "CQ Master Control" switch. Note that all six positions were in series with the master keying and any one of those positions would interrupt that and manually key the selected transmitter. It was arranged such that Position 1 had the final say on whether a transmitter was keyed. This position could interrupt the keying of any other position. Working backwards, Position 2 could interrupt Positions 3 through 6, etc. Because the master keying was in series with all of the positions it went all the way to Position 6 for interruption and then back through all of the positions to Position 1. From CW Position 1 the keying went to the designated 901 F/S Tone Set rack positions.

The system still at RS has a red or green LED to indicate that someone had selected that transmitter for manual keying. When any transmitter was selected at any position to manually key the transmitter all of the LEDs for that transmitter lit up at all of the positions. This helped to keep a second operator from accidentally interrupting another operator's contact, although we hear stories of fights over one operator deliberately "poaching" another operator's contact.

For the MF transmitter keying the circuitry was greatly simplified as only Positions 1 and 2 could key that transmitter and select its frequency. The ZAL (QSY) switch Positions 1 and 2 appear to be directly wired to the appropriate 901 F/S Tone Set rack position.

Because all of the 901 equipment rack positions can take any frequency 901 F/S Tone Set, if there is a problem one can swap individual modules to move a transmitter circuit from one keying line to another keying line. For example, if a particular keying line was intermittent or broken, one other keying line to another transmitter can be disabled by removing the 901 F/S Tone Set transmitter from that rack position and replacing it with the desired frequency 901 F/S Tone Set. This way the desired transmitter can still be keyed but with a different keying line until the Maintenance Department can resolve the problem.

There is also an audio monitor in the 901 equipment rack at FS. The operators learned to patch the audio monitor to any 901 transmitter and listen to the output tone. If it shifted in pitch when keyed there was no problem at RS but the problem resided at the Bolinas transmitter.