• 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.

Problem with RX on VHF Quantar

Status
Not open for further replies.

wgbecks

Active Member
Joined
Jan 17, 2005
Messages
1,145
Reaction score
404
Location
NE Wisconsin
You've received some excellent advise. I'd suggest retesting with the original jumper cables in that the new jumper cables may not be fully shielded as were the original beige colored cables. Improper shielding will allow radiation of the transmitter’s energy to couple into the receive
branch causing desense and possibly into other cables and electronics.
 

LCT123

Member
Joined
Mar 10, 2022
Messages
149
Reaction score
5
You've received some excellent advise. I'd suggest retesting with the original jumper cables in that the new jumper cables may not be fully shielded as were the original beige colored cables. Improper shielding will allow radiation of the transmitter’s energy to couple into the receive
branch causing desense and possibly into other cables and electronics.
Funny you should say that, I am in the middle of bad thunderstorms and I just realized my weather radio will barely receive. It was connected to the quantar receive antenna. Must have got the weather radio like you suggested. I have learned a lot tonight.
 

wa8pyr

Retired and playing radio whenever I want.
Staff member
Lead Database Admin
Joined
Sep 22, 2002
Messages
7,669
Reaction score
4,243
Location
Ohio
That is what I am referring to.
Really needs to do an on site duplexer tune and proper ISO-T test.
Many people think tuning duplexers on a bench and shipping them off are all it takes. Hardly the case.
Feedline choice is also critical in duplex systems.

Concur, align the duplexer. Even being off just a bit will seriously screw up your performance.

I've had experience with those dB Products duplexers, and they didn't hold up too well to shipping; I always had to do a touch-up alignment on site to get it spot on. And if it's the model I'm thinking of there isn't a huge amount of isolation to begin with, which means even a slight bit of misalignment will seriously hork up your repeater performance.
 
Last edited:

prcguy

Member
Joined
Jun 30, 2006
Messages
17,923
Reaction score
13,472
Location
So Cal - Richardson, TX - Tewksbury, MA
Concur, align the duplexer. Even being off just a bit will seriously screw up your performance.

I've had experience with those dB Products duplexers, and they didn't hold up too well to shipping; I always had to do a touch-up alignment on site to get it spot on. And if it's the model I'm thinking of there isn't a huge amount of isolation to begin with, which means even a slight bit of misalignment will seriously hork up your repeater performance.
So what if the receiver is actually bad and you just wasted time tuning a duplexer that didn't need retuning? That's why testing and verifying the receiver is #1 on the list. Once that is verified good and if the problem still remains, only then do you branch out and test the next most likely thing in the system, which may be the duplexer.
 

wa8pyr

Retired and playing radio whenever I want.
Staff member
Lead Database Admin
Joined
Sep 22, 2002
Messages
7,669
Reaction score
4,243
Location
Ohio
So what if the receiver is actually bad and you just wasted time tuning a duplexer that didn't need retuning? That's why testing and verifying the receiver is #1 on the list. Once that is verified good and if the problem still remains, only then do you branch out and test the next most likely thing in the system, which may be the duplexer.

I intended to imply testing the RX first; so many people mentioned it that I didn't really get into it.

But based on my post-shipping experience with those dB Products duplexers, I'd check the alignment on the cans anyway just to make sure.
 

LCT123

Member
Joined
Mar 10, 2022
Messages
149
Reaction score
5
Concur, align the duplexer. Even being off just a bit will seriously screw up your performance.

I've had experience with those dB Products duplexers, and they didn't hold up too well to shipping; I always had to do a touch-up alignment on site to get it spot on. And if it's the model I'm thinking of there isn't a huge amount of isolation to begin with, which means even a slight bit of misalignment will seriously hork up your repeater performance.
The model is a DB4058-A
 
Status
Not open for further replies.
Top