May 2013 – Page 2 – Engineering Radio

New Studio project

It is time, once again, to replace some very old Pacific Recorders BMXII consoles. The Pacific Recorders consoles were very expensive when new, but after 30 years of continuous use, have more than paid for themselves. The replacement console of choice for this installation is a SAS Rubicon. I have installed these units elsewhere and they are the modern equivalent of the PRE BMX.

The heart of the Rubicon system is the 32KD router. Routed audio systems can save a lot of time and effort in a large studio facility installation. Not having to run and terminate multiple analog and digital trunk cables between the rack room and the studio is a huge deal in a six or ten-studio installation project.

The SAS 32KD router and Rubicon console system use a serial TDM bus to communicate and transport audio around. This is a simpler system than packet-switched IP data. Basically, the console surface is a very large, fancy computer control interface. Here are some pictures of the start of the project:

This is the view from the entry door. The furniture was placed last week and the countertop was cut in for the console. The furniture is made by Studio Technology. The pile of yet-to-be-installed equipment:

For monitors, we are using the Tanoy 602p near field monitor placed on the table top above the computer screens. This studio will not have a turret. Turrets used to be necessary to hold things like cart machines and CD players. These days the CD players are used so infrequently that it was decided to put them in the side rack under the counter top. Turrets also take up a lot of counter top space that can be put to better use.

Punch blocks and power connections. The red outlets are isolated ground UPS type, the back outlets are feed by the emergency generator power panel. All electric wiring is inside of the metal conduit. The punch blocks are the inputs to the SAS RIO link unit, one 16-pair analog audio cable and ten category 5e shielded cables. The cat 5e is used for computer and TDM data buss to the router.

The SAS Rubicon console is cut into the counter top and protected by plastic sheets.

Rack room with 32KD routers. This facility has 9 studios total plus a news room with three work areas.

The SAS 32KD router. All audio from the automation systems, satellite feeds and other sources is connected directly to these units. This unit is on line for other studios that have already been converted to the SAS gear.

Well designed circuit boards

Sometimes it is the little things that catch the eye. When I was installing a Nautel transmitter recently, I was admiring the circuit boards used for the transmitter controller. I have seen a few circuit boards that are functional, but leave a little to be desired in the form department. Does it really matter? Perhaps not, but often times those tiny, almost insignificant details come back to bite you. Little things like having the voltage regulator pins correctly placed or putting a toggle switch on the correct side of the board. I have seen both mistakes from another, well known transmitter manufacturer.

Anyway, these are a few photographs of some well designed, well laid out circuit boards.

This is the main controller board.

Surface mount components.

Logic chips.

Nautel XR harmonic filter, part back part is the circuit board

Part of the harmonic trap for the XR series transmitters.

It really is the little things that make big differences. A circuit board under a cover that few people will ever see may seem like a very small and insignificant detail, but I notice and admire these things…

Suppression of ideas

I found this video called Empire of Noise about broadcast radio jamming. It seems to be about ten years old and is a post-cold War documentary about the jamming of radio signals by the USSR, Warsaw Pact counties, and China. It is an interesting look into the extent and expense that governments will go to suppress counter thoughts and ideas.

The video is quite long, and there are stretches of jamming noise that can be annoying, but perhaps that is the point. It is worth the time if interested in history and radio broadcasting. You know what they say about history; those that do not understand history are destined to repeat it.

A few of the highlights:

The former Soviet Union had the most extensive jamming network of anyone on Earth. There were groundwave jamming centers in eighty-one Soviet cities which consisted of approximately 10-15 transmitters each in the 5 KW covering the medium and shortwave frequencies.
Each groundwave jamming station consisted of a transmitter site and a receiver/control site. The receiver site possessed lists of frequencies to monitor, when objectionable material was heard, the jamming transmitters were turned on.
There was a skywave jamming network consisting of 13 jamming stations with 10 or more 100-200 KW transmitters in each. There were some transmitters in the 1,000 KW power range. These were located in Krasnodar, Lvov, Nikolaev, Yerevan, Alma-Ata, Grigoriopol, Sovieck, Novosibrisk, Tashkent, Khanbarovsk, Servdlosk and Moscow (some of these names may have changed). These operated in a similar fashion to the groundwave jammers.
After the sign-off of government stations, Soviet jammers sent a blanketing signal on the IF frequency (most likely 455 KHz) of receivers to effectively block them from receiving any station while USSR government stations were off the air.
Baltic states had 11 jamming stations with approximately 140 transmitters
Ukraine had approximately 300 Jamming transmitters.
Warsaw Pact countries had extensive medium-frequency jamming networks.
It is estimated it takes about 20 times the transmitted power to jam any one signal.

The entire jamming network was hugely expensive to equip and operate, costing several tens of millions of dollars per year.

It is interesting that the US position in all of this was:

Everyone has the right to seek, receive and impart information through any media and regardless of frontiers. Jamming of radio broadcasts is condemned as the denial of the right of persons to be fully informed concerning news, opinions and ideas.

Sounds perfectly reasonable. The free exchange of ideas and information over the internet is something that should be guarded carefully and should not be restricted or censored. Perhaps somebody should inform Congress.