Greetings folks
I have had this Systems Saber for several years and it has worked fine without any issues other than it was never the hottest receiver in the fleet.
It is an H44TUK5170CN
Lately receive went away once in a while and the busy light is flashing. The receiver itself is generating a carrier signal at some frequency that opens the squelch and just sits there silent making even a close signal unable to overcome this mystery carrier.
I gave the radio a "tap"..actually a slight whack and it goes away.
Now, today, it will only go away if I push the Mode button hard...then it is back to normal.... as long as you can hold the button!
Took the case off, cleaned contacts...Seems to be a mechanical thing somewhere.
Has anyone ever run into this?
Any ideas on a fix?
Many Thanks
Dave
Wa9y
S Saber RX Issue-False Internal Carrier
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Re: S Saber RX Issue-False Internal Carrier
AEC fixes those.
Re: S Saber RX Issue-False Internal Carrier
Usual culprits are the connecting pins to the reference oscillator, but any module can cause these problems, as all are using phosphor bronze pins which are prone to physical abuse and snapping. The sockets in the board are also tough to tighten to regain good physical contact. The simplest issue to cure is the main board retention screws, just use the addage: 'finger tight, and a little more', meaning no more than 2-3 INCH OUNCES of torque, not monkey wrench tight!
All the internal modules are retained by screws from the component side of the main board, and those also snug up using the same rule of thumb.
The synthesizer modules have two screws, the receiver module has two, the P.A module has two going through the thin steel framework and into an ALUMINUM heat spreader that is scewed to the frame. The reference oscillator has, or should have, a rubber boot over the oscillator, and if VHF, the filter/detector/switch and LPF are isolated by a spring steel retainer, but only held in the board by their respective pins.
Older type synthesizer modules had a cover that was retained by a single screw, the later versions are a stamped metal variety that is soldered to the board of the synthesizer. The locating pins are tough plastic, but can snap off easily with little physical force.
ALL modules in the radio have thin bronze pins, and they WILL snap if you apply too much lateral force to them,rendering the module defective and unrepairable(usually).
RF band selective filters are located under the receiver module(VHF), the LPF and F.D.S near the top right of the radio, as well as the P.A module are all band selective and must be used in conjunction within the band you are going to use, you can not use a low split LPF with a high split receiver filter, or a mid split F.D.S or P.A. Poor RF performance will be seen and noted if you swap incompatible modules within the radio and expect to get by, you won't.
You can also use a 4X lens to scan the board for poor solder joints and loose components. The main fuse is a 4A PICO fuse, located at the bottom of the frame, near the multi-pin accy. connector, which supports internal and external radio and programming connections to programmers, mics and SVAs.
Lightly clean and check the pins for alignment, they should all be straight with respect to each other, but are bent to support a point contact surface that mates with the flex cable on the bottom of the radio case.
I hope this assists you with locating and curing the issues you suffer from.
All the internal modules are retained by screws from the component side of the main board, and those also snug up using the same rule of thumb.
The synthesizer modules have two screws, the receiver module has two, the P.A module has two going through the thin steel framework and into an ALUMINUM heat spreader that is scewed to the frame. The reference oscillator has, or should have, a rubber boot over the oscillator, and if VHF, the filter/detector/switch and LPF are isolated by a spring steel retainer, but only held in the board by their respective pins.
Older type synthesizer modules had a cover that was retained by a single screw, the later versions are a stamped metal variety that is soldered to the board of the synthesizer. The locating pins are tough plastic, but can snap off easily with little physical force.
ALL modules in the radio have thin bronze pins, and they WILL snap if you apply too much lateral force to them,rendering the module defective and unrepairable(usually).
RF band selective filters are located under the receiver module(VHF), the LPF and F.D.S near the top right of the radio, as well as the P.A module are all band selective and must be used in conjunction within the band you are going to use, you can not use a low split LPF with a high split receiver filter, or a mid split F.D.S or P.A. Poor RF performance will be seen and noted if you swap incompatible modules within the radio and expect to get by, you won't.
You can also use a 4X lens to scan the board for poor solder joints and loose components. The main fuse is a 4A PICO fuse, located at the bottom of the frame, near the multi-pin accy. connector, which supports internal and external radio and programming connections to programmers, mics and SVAs.
Lightly clean and check the pins for alignment, they should all be straight with respect to each other, but are bent to support a point contact surface that mates with the flex cable on the bottom of the radio case.
I hope this assists you with locating and curing the issues you suffer from.
Re: S Saber RX Issue-False Internal Carrier
Typical problems showing up now on the sabers.. What we usually do is heat the board up with the modules.. this should solve the problem.
Circlebat
Circlebat