• 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.

TPL vs DPL tones

Not open for further replies.


Jun 23, 2006
Are there any circumstances as to where a TPL or DPL tone would be preferred over each other in a narrow banded VHF or UHF repeater system or simplex system with the following factors involved.
Mountains, Trees, buildings, ext...
Last edited:


May 23, 2005
Boston, MA
No. DPL and PL behave identically under those circumstances.

In general, I agree.

There is some belief that PL is more susceptible to "roll off" (when a voice or other background sound masks the analog PL, causing subscribers to drop audio unless they have an anti-roll off feature programmed). Supposedly DPL (which is a series of 1s and 0s transmitted at a rate of about 131 Hz) is less susceptible to roll off. I don't know if there are any serious studies to confirm the foregoing.

DPL should be avoided (at least on repeater outputs) in situations where the pool of subscribers includes radios of different makes and models. In such a case, you may find that some subscriber radios use a different convention for "zero departure direction", causing a DPL not to be decoded. The solution in such cases is to program the subscriber's Rx DPL for "invert," but this can play havoc with a "direct" button feature.

If two co-channel users of a repeater frequency pair are close enough that the receivers of one can hear the subscriber inputs of the other, you will have a problem if the PL user uses 131.8 and the other user uses DPL. The DPL system mobiles, when they unkey and send the DPL disconnect code, will cause the 131.8 system to key up momentarily.
Not open for further replies.