Thanks folks...
VHF to VHf cross banding??
Moderator: Queue Moderator
VHF to VHf cross banding??
Anyone know if there is such a thing and if so how do i do this and what am i looking to spend? I am going to be using it in the 151-157 range if that makes a diff...I am new to this so be nice...lol....
Thanks folks...
Thanks folks...
Bill
kc2kuy
Search & Rescue
Kenwood TK-2140
kc2kuy
Search & Rescue
Kenwood TK-2140
VHF
A company by the name of Pyramid makes a system for mobils which they say will do just this, it involves cavities and filters,pretty costly. They were very helpful. Since this is in the public service area, there might be frequencies in your area in the 173 Mhz public safety range, this would make things easier if you can obtain a frequency.
you can acheive what you desire several ways-
cheaply
you can get 2 radios with 16 pin connectors and wrie them to mate with each other - or a controller between them,
you can purchase vechicl repeate units which connect in the same fashion
if you like do the set up for you and send you a ready to use product
cheaply
you can get 2 radios with 16 pin connectors and wrie them to mate with each other - or a controller between them,
you can purchase vechicl repeate units which connect in the same fashion
if you like do the set up for you and send you a ready to use product
I thought you were talking about a crossbad set up- which meant you would operate on 2 diffenrt bands--
thats easy no cavities required.
a vxr1000 can be had brand new with 3 yr warranty for around 4-900 bills - it can be interfaced to many vertex mobile radio with a simple cable - and can be configured to work with other manufacturs as well
of course you would have to build your own cable.
somthing else they offer is a mobile with dual band recive
for the vxr1000
http://www.vertexstandard.com/indexVS.c ... Archived=0
for the mobile with dual recieve
http://www.vertexstandard.com/indexVS.c ... Archived=0[/url]
thats easy no cavities required.
a vxr1000 can be had brand new with 3 yr warranty for around 4-900 bills - it can be interfaced to many vertex mobile radio with a simple cable - and can be configured to work with other manufacturs as well
of course you would have to build your own cable.
somthing else they offer is a mobile with dual band recive
for the vxr1000
http://www.vertexstandard.com/indexVS.c ... Archived=0
for the mobile with dual recieve
http://www.vertexstandard.com/indexVS.c ... Archived=0[/url]
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afterimage84
- Posts: 151
- Joined: Mon Apr 14, 2003 5:09 pm
no one is really answering the question so i will, the vertex is 5-600 and a pyramid will run u about a grand when is all said and done.kc2kuy wrote:Well i need to know whats a good price for one and where can i find one already to go..Again i am looking for the 151-158 range..Thanks...
pin out an old moto like an m10 or something and ur good to go
Suddenly You Were Gone
We run pyramids on our engines for when the repeater is out, they work awsome.
On a seprate note, something i have never understood. If you are running a in band repeater off two antennas with a frequency difference of 10 or 15 mhz why cant this be done with a set of mobiles, Without all the special filtering that pyramid sells.
On a seprate note, something i have never understood. If you are running a in band repeater off two antennas with a frequency difference of 10 or 15 mhz why cant this be done with a set of mobiles, Without all the special filtering that pyramid sells.
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afterimage84
- Posts: 151
- Joined: Mon Apr 14, 2003 5:09 pm
you absolutley can...unless you are pushing out 110 watts...which no one should be in this day and age, yet it still happens...
you don't NEED the filters and such....
you don't NEED the filters and such....
firegood wrote:We run pyramids on our engines for when the repeater is out, they work awsome.
On a seprate note, something i have never understood. If you are running a in band repeater off two antennas with a frequency difference of 10 or 15 mhz why cant this be done with a set of mobiles, Without all the special filtering that pyramid sells.
Suddenly You Were Gone
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007
- Posts: 1546
- Joined: Sat Nov 23, 2002 5:22 am
- What radios do you own?: W7 FPP lowband MaraTrac w/AES
That's an awefully baseless statement. Just because you may not need 110w mobiles, does not mean others around the county do not. Our state-wide VHF system is built around 110w mobiles and 5/8w antennas, and even then it's a haul in some places.afterimage84 wrote:you absolutley can...unless you are pushing out 110 watts...which no one should be in this day and age, yet it still happens...
you don't NEED the filters and such....
Our new in-vehicle repeater setup uses VHF SVR200's into 110w GE Orion's with the appropriate filtering, and it works great. This new in-band setup sounds 1000% better than the old UHF repeater system it's replacing.
Do not make Sig angry...he'll just keep ringing the bell.
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afterimage84
- Posts: 151
- Joined: Mon Apr 14, 2003 5:09 pm
Worse...not at all.
It is NOT a baseless statement. It is a true statement. There is no reason anyone should be running that kind of power (here is the key to the statement) in this day and age...
You are saying you have a state wide system and it a "haul" in some places even with 110 watts? Well thats a system that needs an overhaul. Just out of curosity, have you ever TRIED a lower power radio? I am certian it is an area of the blockheaded "but we have ALWAYS had 110 watts!"
But yes, with that kind of power you definately need the filtering....and some hot dogs to cook on the antenna when you talk.
It is NOT a baseless statement. It is a true statement. There is no reason anyone should be running that kind of power (here is the key to the statement) in this day and age...
You are saying you have a state wide system and it a "haul" in some places even with 110 watts? Well thats a system that needs an overhaul. Just out of curosity, have you ever TRIED a lower power radio? I am certian it is an area of the blockheaded "but we have ALWAYS had 110 watts!"
But yes, with that kind of power you definately need the filtering....and some hot dogs to cook on the antenna when you talk.
Suddenly You Were Gone
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007
- Posts: 1546
- Joined: Sat Nov 23, 2002 5:22 am
- What radios do you own?: W7 FPP lowband MaraTrac w/AES
I'm with you guys.afterimage84 wrote:Worse...not at all.
It is NOT a baseless statement. It is a true statement. There is no reason anyone should be running that kind of power (here is the key to the statement) in this day and age...
You are saying you have a state wide system and it a "haul" in some places even with 110 watts? Well thats a system that needs an overhaul. Just out of curosity, have you ever TRIED a lower power radio? I am certian it is an area of the blockheaded "but we have ALWAYS had 110 watts!"
But yes, with that kind of power you definately need the filtering....and some hot dogs to cook on the antenna when you talk.
There are enough tower sites ( ~70) that I'm sure 50w radios would work just fine in 95%+ of the state. As mentioned, there seems to be a mentality in the communications division that they need to make the base stations deaf as posts, therefore needing the power from the cars.
Using a portable is useless unless you are within 5 miles (visually) of the tower in question. I think that poses more of an officer safety issue than anything, but again all hail the mobile repeater.
In my particular area, there are 2 hammie repeaters that are co-located on the tower with the state equipment. In both cases, the hammie equipment talks and hears better with the same output power (~100w) and similar antennas at the same height, or slightly higher. Everything is commerical for both applications (RF equipment, antennas etc).
I would change it if I could, but I can't...not my job. I'm an end-user.
As for there being no need for 110w anymore, that isn't true. If you are still running lowband VHF simplex (like a lot of places in the plains/midwest still do), you need all the power you can get.
Do not make Sig angry...he'll just keep ringing the bell.
In-band VHF repeater system....
Most certainly CAN be accomplished with even low power radios, I've built several ham repeaters for folks using the garbage Hamtronics boards with TCXOs and dual whips for TX/RX with a single BpBr can to notch the IMD products and I can take a 2 watt HT over a mile away from the car and still hear my output on another HT held in my hand.
All things considered, even a 10 watt mobile repeater is easy to design for vehicular use IF the proper precautions are dealt with.
No fancy duplexers needed, just a single can is all you should require, along with a moderate gain GaAs FET preamp AFTER the filter on the RX side feeding the receiver.
Good grounding and shielding is a must in any environment, and the vehicle is no different.
The cabinet this was built inside of had partitions for all modules, including feedthroughs for DC, audio, RF and control signals if using even a cheap controller, or just an audio level switch to engage the transmitter.
I use a power mosfet for switching the TX and mic audio lines and this setup works like a charm and has yet to suffer from any sort of heat related issues or RF induced problems.
Every DC line and audio level line was filtered and used double shielded cabling with ground points along the lines to prevent RF ingress and keep the audio signals free of spurs.
Old Motorola MSY repeaters had a handy 3-cavity filter in the 12 watt (on UHF machines) transmitter section that tunes easily in the 150 Mhz range and is a snap to get resonant on the frequency of choice to use as a filter on the rceiver input, ahead of the pre-amp.
You can also locate a low power circulator and place it on the transmitter to prevent IMD products of desensing your input while keeping stray RF off the air.
Remember to terminate the circulator with a load that is at least twice the level of RF you intend to run, and make certain it is rated for continuous duty, and not intermittent, in case the transmitter remains keyed due to some form of failure, and if possible, bolt the load to the housing for added heatsinking.
That's all I have for now...
Good luck in your endeavor!
P.S. You should be able to construct this easily using readily available radios and components for well under $600.00 and have a kick butt system.
Remember the K.I.S.S analogy...it does work.
Some things are better when kept to minimal requirements that meet the goals you have.
All things considered, even a 10 watt mobile repeater is easy to design for vehicular use IF the proper precautions are dealt with.
No fancy duplexers needed, just a single can is all you should require, along with a moderate gain GaAs FET preamp AFTER the filter on the RX side feeding the receiver.
Good grounding and shielding is a must in any environment, and the vehicle is no different.
The cabinet this was built inside of had partitions for all modules, including feedthroughs for DC, audio, RF and control signals if using even a cheap controller, or just an audio level switch to engage the transmitter.
I use a power mosfet for switching the TX and mic audio lines and this setup works like a charm and has yet to suffer from any sort of heat related issues or RF induced problems.
Every DC line and audio level line was filtered and used double shielded cabling with ground points along the lines to prevent RF ingress and keep the audio signals free of spurs.
Old Motorola MSY repeaters had a handy 3-cavity filter in the 12 watt (on UHF machines) transmitter section that tunes easily in the 150 Mhz range and is a snap to get resonant on the frequency of choice to use as a filter on the rceiver input, ahead of the pre-amp.
You can also locate a low power circulator and place it on the transmitter to prevent IMD products of desensing your input while keeping stray RF off the air.
Remember to terminate the circulator with a load that is at least twice the level of RF you intend to run, and make certain it is rated for continuous duty, and not intermittent, in case the transmitter remains keyed due to some form of failure, and if possible, bolt the load to the housing for added heatsinking.
That's all I have for now...
Good luck in your endeavor!
P.S. You should be able to construct this easily using readily available radios and components for well under $600.00 and have a kick butt system.
Remember the K.I.S.S analogy...it does work.
Some things are better when kept to minimal requirements that meet the goals you have.
Repeater
I recently set up the following bi directional mobil system at 159.**** / 151.**** using the following:
Motorola CDM 1250 VHF 45 watts
Motorola M1225 VHF set at 8 watts
Motorola HLN3333 Repeater rick
2 quarter wave antennas mounted 30 inches apart on the roof top.
Works like a charm, no intermod or distortion.
Was able to set up so that all equipment comes on when ignition switch power on the relay (50 amp).
Motorola CDM 1250 VHF 45 watts
Motorola M1225 VHF set at 8 watts
Motorola HLN3333 Repeater rick
2 quarter wave antennas mounted 30 inches apart on the roof top.
Works like a charm, no intermod or distortion.
Was able to set up so that all equipment comes on when ignition switch power on the relay (50 amp).
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afterimage84
- Posts: 151
- Joined: Mon Apr 14, 2003 5:09 pm
Re: In-band VHF repeater system....
at the end of this post there is the KISS but what your running on and on about is sooooo not KISS simple. well, may be to YOU it is, but to some others it may not be.
KISS simple, Buy a pyramid, Program it once, Plug it in, DONE...
KISS simple, Buy a pyramid, Program it once, Plug it in, DONE...
AEC wrote:Most certainly CAN be accomplished with even low power radios, I've built several ham repeaters for folks using the garbage Hamtronics boards with TCXOs and dual whips for TX/RX with a single BpBr can to notch the IMD products and I can take a 2 watt HT over a mile away from the car and still hear my output on another HT held in my hand.
All things considered, even a 10 watt mobile repeater is easy to design for vehicular use IF the proper precautions are dealt with.
No fancy duplexers needed, just a single can is all you should require, along with a moderate gain GaAs FET preamp AFTER the filter on the RX side feeding the receiver.
Good grounding and shielding is a must in any environment, and the vehicle is no different.
The cabinet this was built inside of had partitions for all modules, including feedthroughs for DC, audio, RF and control signals if using even a cheap controller, or just an audio level switch to engage the transmitter.
I use a power mosfet for switching the TX and mic audio lines and this setup works like a charm and has yet to suffer from any sort of heat related issues or RF induced problems.
Every DC line and audio level line was filtered and used double shielded cabling with ground points along the lines to prevent RF ingress and keep the audio signals free of spurs.
Old Motorola MSY repeaters had a handy 3-cavity filter in the 12 watt (on UHF machines) transmitter section that tunes easily in the 150 Mhz range and is a snap to get resonant on the frequency of choice to use as a filter on the rceiver input, ahead of the pre-amp.
You can also locate a low power circulator and place it on the transmitter to prevent IMD products of desensing your input while keeping stray RF off the air.
Remember to terminate the circulator with a load that is at least twice the level of RF you intend to run, and make certain it is rated for continuous duty, and not intermittent, in case the transmitter remains keyed due to some form of failure, and if possible, bolt the load to the housing for added heatsinking.
That's all I have for now...
Good luck in your endeavor!
P.S. You should be able to construct this easily using readily available radios and components for well under $600.00 and have a kick butt system.
Remember the K.I.S.S analogy...it does work.
Some things are better when kept to minimal requirements that meet the goals you have.
Suddenly You Were Gone