• To anyone looking to acquire commercial radio programming software:

    Please do not make requests for copies of radio programming software which is sold (or was sold) by the manufacturer for any monetary value. All requests will be deleted and a forum infraction issued. Making a request such as this is attempting to engage in software piracy and this forum cannot be involved or associated with this activity. The same goes for any private transaction via Private Message. Even if you attempt to engage in this activity in PM's we will still enforce the forum rules. Your PM's are not private and the administration has the right to read them if there's a hint to criminal activity.

    If you are having trouble legally obtaining software please state so. We do not want any hurt feelings when your vague post is mistaken for a free request. It is YOUR responsibility to properly word your request.

    To obtain Motorola software see the Sticky in the Motorola forum.

    The various other vendors often permit their dealers to sell the software online (i.e., Kenwood). Please use Google or some other search engine to find a dealer that sells the software. Typically each series or individual radio requires its own software package. Often the Kenwood software is less than $100 so don't be a cheapskate; just purchase it.

    For M/A Com/Harris/GE, etc: there are two software packages that program all current and past radios. One package is for conventional programming and the other for trunked programming. The trunked package is in upwards of $2,500. The conventional package is more reasonable though is still several hundred dollars. The benefit is you do not need multiple versions for each radio (unlike Motorola).

    This is a large and very visible forum. We cannot jeopardize the ability to provide the RadioReference services by allowing this activity to occur. Please respect this.
  • Effective immediately we will be deleting, without notice, any negative threads or posts that deal with the use of encryption and streaming of scanner audio.

    We've noticed a huge increase in rants and negative posts that revolve around agencies going to encryption due to the broadcasting of scanner audio on the internet. It's now worn out and continues to be the same recycled rants. These rants hijack the threads and derail the conversation. They no longer have a place anywhere on this forum other than in the designated threads in the Rants forum in the Tavern.

    If you violate these guidelines your post will be deleted without notice and an infraction will be issued. We are not against discussion of this issue. You just need to do it in the right place. For example:
    https://forums.radioreference.com/rants/224104-official-thread-live-audio-feeds-scanners-wait-encryption.html

Scanner / Speaker Compatibility / Ohm Value

Status
Not open for further replies.

Julian1

Member
Premium Subscriber
Joined
Feb 13, 2002
Messages
836
Location
Birmingham, AL
OK........... I'm not an electrician, but I do love my scanner.

Please answer in layman's terms....plain english.

I run an external speaker on my Uniden 785 in my car.

When I look at Motorola or GE speakers on eBay, I see a range of Ohm ratings along with the wattage rating of the speaker.

Ohms as I recall is a measurement of resistance.......hmmm??? I have seen formulas for Ohms law. (If I break Ohms law, do I get a ticket??? LOL) Sorry.... Lest I digress.........

How important is the Ohm rating of a speaker when applying it to a scanner or other receiver????? Does the sanner audio "system" have a specific Ohm rating?

Thank you in advance for your help.
Julian
 

kb5udf

Member
Joined
Apr 7, 2004
Messages
521
Location
Louisiana
Ohm Ranges Frequently Nominal

From my readings most speakers/receivers ohm ratings are nominal/in name only at least to a point. Generally, interchanging 4 ohm speakers with amps/radios made for
8 or six is ok. Although if it were 2 ohm I'd be a little less confident at least in home stereo applications. In any event I'm told that the ohm rating of a speaker is nominal
because the actual value depends quite widely depending on the audio frequency in question.

Bottom line, hooking just about any speaker within reason, other than something like a
dual voice coil subwoofer, should be just fine for your scanner.

Jean
 

RevGary

Senior Tropical Storm Analyst, TSRC, in Alabama
Joined
Oct 22, 2005
Messages
790
Hey, Julian - look at this link for BC 785 spec's and note that the internal speaker is 8 ohm. Since the miniplug disconnects the internal speaker when an external is used, that circiut would be 'happiest' with an 8 ohm external load. That will give you roughly the same characteristics as the original, but will allow you to position it so it can be heard better, in a vehicle.

Use an 8 ohm, 3 watt (or higher) rating on the external and happy listening. The second link shows the one that we are using in several of our vehicles. They have noise cancelling and they are bulletproof...

http://radioproshop.com/uniden/unidenbc785d.htm

http://www.grove-ent.com/spk07.html
 

N1508J

Member
Joined
Dec 21, 2005
Messages
88
Location
Not allowed...infraction.
Julian,
Look at your other post for my answer to your question.

Also, there is a BIG difference between DC ohms and AC impedance in ohms. Think, why is some coax cable 50 ohms and other 72 ohms??? You can't measure any resistance (ohms) on the coax between the conductors with your ohmmeter can you?? An 8 ohm speaker could very well have an 8 ohm voice coil, but it could just as well have a 25 ohm DC resistance voice coil!!!!. One is an impedance otherwise known as Z, in ohms, and the other is a DC resistance in ohms ,otherwise known by the Greek letter Omega! In short, if the radio's audio amp is designed for a 8 ohm IMPEDANCE speaker, it's best your external speaker be just that. If you use a lower impedence speaker, then the audio circuit, particularly the active componets, will overheat and possibly fail! If you use a higher impedance speaker, the radio won't care but the audio will continue to become lower the higher you go in impedance.
 
Status
Not open for further replies.
Top