Radio Pictures – KFWB Postcard

Radio is a funny thing. Once it gets under your skin you’re done for, it has you for life.

And I am talking about real radio, the kind that goes through the air and is freely available to anybody within range. Streaming on the internet is fine, but it ain’t radio. If you’re a radio person, only real radio floats your boat.

One of the things that happens to you when you get bugged by radio is that you accumulate ‘radio stuff.’

Among the stuff I’ve accumulated are various postcards and radio related ephemera.

As we continue to test AM1700 Radio Richmond and make progress on the studio I thought I would take some time to share some pictures with you.  Here we have a post card depicting an early KFWB Los Angeles.

KFWB Postcard

KFWB took to the air in 1925 under the ownership of Sam Warner. This picture shows the hammock antenna strung between two self supporting towers in front the Warner Brothers Motion Picture Studios in Los Angeles, Ca.

The station is still on the air today with the same call letters broadcasting with 5Kw on 980Khz.

I’ll share more postcards and photos of radio stations and facilities over the next few weeks. I hope you enjoy them.

Radio Richmond – Testing Begins!

This past weekend I installed one of the Hamilton Rangemaster AM1000 transmitters on the roof of my house. The installation meets the requirements for power, antenna, and ground lead length making it a legal unlicensed station per the Part 15.219 rules.

I have good news and bad news.

The bad news first – nighttime coverage in unimpressive. After just a couple of blocks there is noticeable interference from distant stations on 1700 khz. This was not a total surprise however, I expected XEPE “San Diego” (actually Northern Mexico) to give me some trouble. And of course, the noise floor is pretty high in spots around here.

The worst noise problems are near overhead MUNI wires and near businesses. These noise problems are prevalent day and night.

The good news: Daytime coverage is considerably better.

I did an afternoon “range check” walk around the neighborhood with a portable radio. For those keeping score, it was a Grundig Yacht Boy 400. This isn’t most sensitive radio in the AM band but it’s OK. Most car radios are better in the AM broadcast band. Shown below is the “coverage area”.

Radio Richmond Daytime Pattern

Area where Radio Richmond can be heard comfortably with possibly some careful orienting of your radio.

I put it in quotes because it is possible to pick up the signal outside these boundaries. The marked area shows where the station could be heard with comfortable listening. In some spots you’d have to re-orient the radio for best reception but the signal was not hard to hear.

The area covered by the daytime pattern is approximately 0.2 square miles. That doesn’t sound like much, but given the population density of the Richmond District, this coverage represents a potential audience of about 5600 of my closest neighbors. Not too shabby!

I think I could achieve better coverage with a better ground. The short ground lead connects to the steel pipe the AM1000 is mounted on. However, I don’t know if there is electrical continuity with earth. And even if it did connect to “earth”  the soil around these parts is basically just sand. It’s not the good conductive soil that makes AM radio signals sing.

My first goal is full weekend, daytime programming.  I’ll publish a schedule when I can reliably meet that programming threshold.

What’s happening with the station anyway?

It’s now March 1st, 2014 and it seems like development of the station is moving at a glacial pace, which it is. The fact of the matter is that this station is a hobby, and as such it gets afforded hobby time resources.  That means I work on it when I can get to it. Also there is competition from other hobbies and responsibilities.

But I have not given up on Richmond Radio.

In addition to the Rangemaster AM1000 transmitters I talked about in the previous post, I have added to the station equipment an Inovonics 222 AM processor. This unit provides a low pass filter, pre-emphasis, and asymmetrical peak limiting. My main interest is with the peak limiter – it is capable of driving the Rangemasters to 125% positive modulation which helps distribute the power to where it will do the most good in terms of transmission range.

inovonics_222

I’ve experimented a little with running the audio from the source through a compressor (MDX1600) then through the Inovonics to the transmitter. However, finding the right distribution of gain and settings on the compressor was hard. I remained challenged to find a combination of settings that sounds good.

In fact, the best sound I got was by omitting the compressor and simply running the program from the source through the Inovonics to the Rangemaster. So my plan is to go with that setup.  Maybe the MDX will find a home in a production capacity, but for now it is out of the airchain.

The next step must really be to get one of the AM1000’s mounted on the roof and tuned up. This is harder than it sounds because roof access is not easy where I live. Furthermore, I need to get some four conductor shielded twisted pair cable to run audio and DC power to the transmitter on the roof. Then at least I can see what my transmission range is and start airing some programs.

I want to point out that I am not too hung up on the subject of transmission range. Yes, I want to get out as far as possible with the limitations placed on me  by my equipment and running Part 15.219 legally but I’d have to say that distance is not a primary goal.

I am having fun assembling the station, and I am building transmission capacity. I am learning how much is involved in simply getting a professional sounding signal on the air and I feel that developing the ability to do that is worthwhile.

Who knows what the future will bring, but isn’t it better to be prepared to serve your neighborhood or community in times of need rather than try to develop that ability during an emergency? And the preparedness goes both ways. Even if your range is truly limited, you still want your neighbors to know about your station and how to tune in so that when an emergency hits they might remember you as a resource.

So really I just consider my efforts now as preparation. And if, as I prepare, my neighbors can hear my station and get some information or entertainment from it then I think it is time well spent.

Hopefully the next post will announce on-air tests.

Catch ya’ in a bit …