Search found 77 matches

by Fran3
Tue Mar 03, 2020 7:14 am
Forum: AM Radio
Topic: What type of "bridge" is used to tune Directional Arrays?
Replies: 3
Views: 230

What type of "bridge" is used to tune Directional Arrays?

1 - What type of device is used to tune an AM directional array. I think it is some sort of impedance bridge that works under power but I'll be darn'd if I can remember what it is called... and who makes them or who made them. 2 - Is there a procedure online or elsewhere that would walk one through ...
by Fran3
Fri Jan 03, 2020 5:23 pm
Forum: FM Radio
Topic: How to feed mono only audio into base band input on tx?
Replies: 14
Views: 558

Re: How to feed mono only audio into base band input on tx?

Is there any "open source" audio processor that might work to get this project started?

Thanks for the help folks.
by Fran3
Fri Jan 03, 2020 8:12 am
Forum: FM Radio
Topic: How to feed mono only audio into base band input on tx?
Replies: 14
Views: 558

Re: How to feed mono only audio into base band input on tx?

We want the FM translator to broadcast only in mono... we do not want to broadcast in stereo. This is a test of an FM translator for an AM station so the FM transmitter will be rebroadcasting the am signal... By "process" I assume you mean create the standard "MPX baseband" signal that is fed to FM ...
by Fran3
Thu Jan 02, 2020 3:58 pm
Forum: FM Radio
Topic: How to feed mono only audio into base band input on tx?
Replies: 14
Views: 558

Re: How to feed mono only audio into base band input on tx?

1uf Cap in series with the audio "hot" 75 ohm resistor from audio "hot" to ground Audio in ------ C1 --------|----------- Audio out with 75us pre-emphasis .............................R1 -----------------------------|----------- OK? Note... dashes = wires dots = spaces to force R1 into position :-) ...
by Fran3
Thu Jan 02, 2020 3:15 pm
Forum: FM Radio
Topic: How to feed mono only audio into base band input on tx?
Replies: 14
Views: 558

How to feed mono only audio into base band input on tx?

We are going to be testing an FM transmitter for use as a translator. As I understand it the unit expects an MPX baseband audio signal at the input.... which as I understand it is... 0 to 15khz = mono audio meaning the left channel sum'd with the right channel... aka L+R 19khz pilot signal 23 to 38k...
by Fran3
Thu Aug 29, 2019 3:29 pm
Forum: Ask the Engineers
Topic: Where are EAS Location Codes ?
Replies: 2
Views: 175

Where are EAS Location Codes ?

I'm checking the programming on an EAS system that has been in service for a long time and want to make sure the location codes meet the current standard... BUT... where is a list of the current state and county codes for use in an EAS system? As I read it here... https://www.nist.gov/sites/default/...
by Fran3
Wed Jul 17, 2019 7:58 am
Forum: Ask the Engineers
Topic: Rohn 55 to Rohn 25 transition or adapter
Replies: 3
Views: 229

Rohn 55 to Rohn 25 transition or adapter

Any suggestions on how to transition from Rohn 55 to Rohn 25 ? We called Rohn and they said they did not have such. Reason for asking is we have a Rohn 55 tower and some surplus Rohn 25 sections. We want to extend the tower 30 to 60 feet and the Rohn 25 is handy and in good shape. Total tower height...
by Fran3
Mon Jul 01, 2019 1:31 pm
Forum: Everything else
Topic: Which Android App to Record Interview directly on phone?
Replies: 2
Views: 274

Which Android App to Record Interview directly on phone?

We want to be able to do phone interviews using a Android Smart Phone and record them directly to the phones memory card for later transfer to our system and later broadcast and/or pod cast. I see a number of Android App's that allow recording a conversation but I thought I'd ask you guys if you had...
by Fran3
Fri Jun 07, 2019 10:47 am
Forum: AM Radio
Topic: AM Transmitter Shelter
Replies: 6
Views: 556

Re: AM Transmitter Shelter

Coax to towers and sample lines will remain the same. New location 50 to 100 feet due south of current location and our tower guy tells us he can easily move the existing lines... so, for now, we are hopeful that is true... else... more $$$. (He has also done complete installations so he will be phy...
by Fran3
Wed Jun 05, 2019 8:07 am
Forum: AM Radio
Topic: AM Transmitter Shelter
Replies: 6
Views: 556

AM Transmitter Shelter

Looking for suggestions on "budget" (new or used) shed/shelter to house a 5kw AM transmitter, 3 phase cabinets, and two or three standard size equipment racks.

This is for a possible transmitter relocation from inside the studio building to the new shed/shelter near the center tower base.
by Fran3
Tue Apr 30, 2019 11:50 am
Forum: Radio Studio Engineering
Topic: Audio cable for AM transmitter site? Star Quad or Ethernet or What?
Replies: 22
Views: 1021

Re: Audio cable for AM transmitter site? Star Quad or Ethernet or What?

Belden 8451. I'm ordering it today. FYI, free shipping using Amazon Prime.
by Fran3
Mon Apr 29, 2019 10:35 am
Forum: Radio Studio Engineering
Topic: Audio cable for AM transmitter site? Star Quad or Ethernet or What?
Replies: 22
Views: 1021

Audio cable for AM transmitter site? Star Quad or Ethernet or What?

What cable do you guys suggest for running balanced audio around the building when the studio is co-located with the transmitter? Long run case... - In this case we have two studio's... - one requires a run of about 20-feet... - the other requires a run of about 50 feet. Short run case... - In studi...
by Fran3
Sun Apr 07, 2019 2:30 pm
Forum: Radio Studio Engineering
Topic: How to bridge 600 ohm balanced line to monitor or record?
Replies: 7
Views: 621

Re: How to bridge 600 ohm balanced line to monitor or record?

Thanks again for the help and suggestions.

I'm using the term "node" to designate a point along the mono analog audio path.

We will continue to work on this until we track the culprit down.

I'll try to post back when we figure out what the heck is going on.
by Fran3
Sun Apr 07, 2019 8:40 am
Forum: Radio Studio Engineering
Topic: How to bridge 600 ohm balanced line to monitor or record?
Replies: 7
Views: 621

Re: How to bridge 600 ohm balanced line to monitor or record?

Thanks folks. Studio and transmitter are co-located in the same building. We (think) we have eliminated the computer automation system stuttering as it also streams and the stream seems (we think) to sound fine. However, since the interruptions are only a few seconds long... and occur only every now...
by Fran3
Sun Apr 07, 2019 6:29 am
Forum: Radio Studio Engineering
Topic: How to bridge 600 ohm balanced line to monitor or record?
Replies: 7
Views: 621

How to bridge 600 ohm balanced line to monitor or record?

Having a problem with on air audio intermittently being interrupted. Occurs randomly for a few seconds every few hours on air. We are unsure where the problem is occurring so to try and pinpoint it we want to be able to tap on to the audio at different points along the way to either listen or record...