I am not sure what the purpose of this is for, or who put it there:
Mystery 66 block
The mystery type 66 punch block is mounted high up on the wall in the hallway. The contractors are removing the carpeting on the wall and drywalling over it, when they reached this, they just cut around the block and kept going. On one side is a Teflon jacketed 25-pair category 3 phone wire, which goes back to the rack room, somewhere. The rack room is a little disorganized and it is difficult to mess around with the various bundles of wire without knocking a station off the air.
On the other side is a bunch of 1N1004 diodes punched down. Perhaps some sort of door light circuit? Or maybe a remote channel selector for one of those old Scientific Atlanta 7300 series satellite receivers? I don’t know.
I used my big wire loppers and cut the cable. There were no sparks and everyone stayed on the air. I pulled the whole thing down and removed it, so the drywall contractor can finish patching the holes.
The entire facility is getting gutted and redone soon.
I love the sound of these units when coupled with an Optimod 8100A. Many people have (or rather, had) difficulty setting these things up. I found them to be very easy to deal with, just follow the instruction manual. If that doesn’t sound good, then there is something wrong with the unit. Over the years, there are only a few consistent problems. The first thing is with the voltage regulators. They have heat sinks attached with nylon screws. The screws get brittle and fall apart, making the regulator overheat and go bad. I have taken to replacing the nylon screws, and if the heat sink has fallen off, the entire regulator. There are also a few electrolytic capacitors in the power supply and on the audio board, it is always a good practice to replace those. Otherwise, unless the unit has been blown up by lightning, it should work.
As for set up, follow the directions in the manual:
Bypass the units using the bypass switch
Turn on the onboard pink noise generator
Using the test ports on the front of the unit, plug a Simpson 260 VOM set on 2.5 VAC important: use the ground port on the front of the unit, not the case
For use with an Optimod 8100A, using the dB scale on the Simpson 260, set all the bands for a 4.0 reading. Set the density to 3/4.
Turn off the pink noise generator and switch out of bypass mode.
Make sure the levels in the studio are where they should be.
Adjust the input gain so the “Buffer Active” light does not come on during normal-level programming.
Adjust the output levels so that the input buffer on the Optimod reads between -7 and -3 vu.
The rest of the settings are on the Optimod:
Clipping = 0
HF limiting = 5
Release time = 2
Bass coupling = 2
Gate = 0
Set the input attenuators for about 10 dB total gain reduction, with peaks around 15 dB or so.
Then set the L-R null. To do this, make sure the program material is in mono, then adjust the L or R input attenuator for minimum reading. Also, if the Audio Prism has PR-1 (phase rotators) installed, bypass the phase rotator in the Optimod. There is also a replacement card 5 made by Gentner called the RFC-1 for the Optimod 8100A. I notice little difference between a stock Optimod and an RFC-1 Optimod.
That is a good starting point. Most people are quite happy with this, but if needed, the high and low settings on the Prism can be adjusted slightly to suit the station equipment. When properly adjusted, this equipment rides gain, and adds a certain amount of loudness, while keeping the programming material natural sounding. Further, unlike some “modern” air chain processors, it does not boot up and it does not occasionally lose its mind, requiring a reboot.
The best paragraph in the manual, or any broadcast equipment manual is this:
There is a wealth of information available in the LED display. A few minutes of watching them in reduced light (emphasis added) while listening to a familiar program input will greatly help in understanding their action.
It will also greatly enhance your buzz, dude. It was the 70’s.
Richard Dillman, who is the driving force behind the Maritime Radio Historical Society (MRHS) has produced a show on KWMR called “Incredible Radio Tales.” This is a show that talks about the various sounds heard on the radio, both natural and man-made. Many of the shortwave frequencies are used for “utility” uses.
He does a great job explaining things like Skyking, numbers stations, and so forth. It is a great show, I can imagine this story being told on Halloween.
You can listen to the first episode here, it’s about an hour long:
I see this statement being made on various forums, blogs, and other places. As some would like to believe, the problem with HD radio is that people don’t like change. A Look at the early days of FM radio in the 1950s is a good example of this. FM radio took decades to catch on, HD Radio is no different. Currently, HD Radio is experiencing “growing pains” and the occasional “bump in the road.”
Except; no, not really.
Here is a side by side comparison:
Problem/issue
FM radio 1950
HD radio 2010
Implementation of technology
A new band was created and new radios containing the old (AM) and new FM band were manufactured. During the experimental phase (1937-47), the frequencies were between 42-50 MHz. This changed to 88-108 MHz in 1947. Uptake on new radios was slow due to a frequency shift.
Existing AM and FM frequencies were utilized using “Hybrid” mode. This entailed changing existing channel bandwidths arbitrarily. New receivers with the HD Radio chipset needed to receive broadcasts.
Funding
FM radio was implemented by broadcasters who, for the most part, bore the brunt of the costs themselves.
Consumers are generally unaware of HD. Those that are become disappointed with the lack of additional programming choices and poor receiver performance
Creation of interference
FM broadcasting created no interference to any other broadcasting station when it was rolled out
HD radio has created many interference problems, especially on the AM band at night, where skywave propagation makes adjacent channel stations bear the brunt of exceeded bandwidths. FM is prone to co-carrier interference from higher digital power levels created to solve poor reception issues in addition to adjacent channel interference to adjacent FM broadcasters from exceeded bandwidths.
Lack of consumer awareness or interest
HD radio offers a slight improvement to “CD quality” which is hard for the average listener to tell apart from typical analog FM. AM offers increased audio quality over analog, however, due to reception problems, AM receivers often lose data synchronization and return to the analog signal, creating up/down listening experience most find annoying.
Consumers were generally aware of FM radio, however, the FCC created a major stir when forcing FM broadcasters to move from their original frequency band of 42-50 MHz to 88-108 MHz. This move rendered obsolete many FM radios and caused hard feelings to amount early FM radio fans.
Technical reception problems
FM stations began broadcasting with low power levels and horizontally polarized antennas. Radio was not yet a mobile medium. Many FM listeners needed to install outdoor antennas on their homes to get reception. Radio listeners were willing to undertake this for good reception.
HD power levels are less than needed to have reliable reception in buildings and mobile listening environments. A 6 to 10 dB increase has not effectively been implemented nor solved the problem
Audio quality
FM broadcasting is markedly superior to AM broadcasting in the areas of noise reduction and fidelity.
HD radio offers a slight improvement to “CD quality” which is hard for the average listener to tell apart from typical analog FM. AM offers increased audio quality over analog, however, due to reception problems, AM receivers often loose data synchronization and return to the analog signal, creating up/down listening experience most find annoying.
Auxillary services, additional channels
FM broadcasting did not have any such features in 1950
HD radio offers the choice of 2 additional channels for programming. These channels are taken from the existing bandwidth/bit rate of the digital carrier and are a lower quality than the main channel. In addition to that, there is a data channel that can be used to display song titles and such
Programming
HD Radio main channel is the exact duplicate of its analog signal. HD-2 and HD-3 channel offer a variety of programming choices including simulcasts of AM stations, retransmissions of co-owned out-of-market stations, syndicated satellite programs, and occasionally a niche format.
During the early FM development and implementation, the only competing electronic medium was AM radio
Electronic Media availability
HD radio has enjoyed a rubber stamp environment where large businesses and the FCC work together to re-write interference regulations with no regard for technical consequences.
The choices of electronic media are wide and diverse. These include TV, satellite radio, internet, 3G wireless, mp3 players, AM and FM radio
Regulatory environment
The FCC staff was filled with ex or future RCA employees, who were interested in the status quo, thus keeping FM from becoming too big too fast and competing with the roll out of RCA’s television technology. Therefore it was hobbled with low power levels and a bizarre station class structure
The FCC staff was filled with ex or future RCA employees, who were interested in the status quo, thus keeping FM from becoming too big too fast and competing with the rollout of RCA’s television technology. Therefore it was hobbled with low power levels and a bizarre station class structure
The FM rollout in the late forties and early fifties is vastly different from the HD Radio rollout in the zero zeros. Due to fear of competition and patent disputes, RCA in conjunction with the FCC did all they could to squash the new technology. That is why FM radio took so long to be accepted by the general public. For those not versed with the history of FM development and FM broadcasting in the US, see Empire of the Air, by Tom Lewis. See also: Edwin H. Armstrong. It is a good read for those radio obsessed.
HD Radio is failing because the consumer is not buying it, I see little to change their mind.
