This manual is downloaded from the FoxTango site, Yaesu. FRG HF Receiver. Survival Guide. Revision 2 march. If you want to work on your FRG, it is a must to have the manuals and schematics. See: The manuals are very informative and deal. The purpose of this manual is to provide the reader with information critical to the nance of the FRG general coverage communications receiver.
|Published (Last):||23 August 2005|
|PDF File Size:||15.54 Mb|
|ePub File Size:||8.51 Mb|
|Price:||Free* [*Free Regsitration Required]|
I mounted all on a piece of epoxy experiment board, see the pictures and schematic below. Just check for a By submitting a comment, you are declaring that you agree with these rules:. I did a test, the plastic was not affected by the thinner. The circuit design is ok, but can be improved. Personally, i did not like the result, and changed this elco back to uF.
Close inspection discovered some more shorts between solder joints. If they fail manuak there can be a reason they fail again in the future, and putting in a socket is cheap and makes life easier when the need arise. Web Master Fox Tango International. In another case I found diode D43 that was no diode anymore but a resistor of 5k-ohm, the on and off time of the display was the frg-77000, and there was a curious frequency display.
I had the counter still connected. So I took the VFO out the receiver, a very easy job, although it means the removal of all knobs, scales and front panel. Standby 10W 10W ON: To repair the board, it was necessary to take the PLL board out of the receiver. I have to see what I buy.
First I had to construct ,anual new power supply, because the owner had thrown away the burned board, but fortunately had still the original transformer, complete with burn marks and burned wires.
I wanted to use the original features, and designed a board, centered around a trustful LM regulator IC and a NPN power transistor.
Compared with my other FRG, the signals were almost the same strength, so I spent some time to clean the chassis, knobs and front panel, and rebuild the set. I use it also for repainting and refill markings on boat anchor receivers, like the RA and Racal. After studying the circuit diagram I found that the Memory Fine control is nothing more than a voltage divider, the output is used to tune a varicap in the memory unit.
I had a recently a receiver with a bad display driver, and obtained another from Internet as spare, with a defect. Yaesu uses a amber filter, to change the color in the style of all their equipment of the time FTZD, FT This tube has a filament, and has in the long run the same problem as all tubes: Using the clock was no problem, but the switch could not change to the frequency mode, it still displayed the time.
With the condenser fully open I had a frequency of around Khz. After modification the receiver is to re-align according the service manual, for the best results. I made a truth table of the 6 input pins of the MB, and soon discovered that pin 15 had no true 0 or 1, but had always a voltage of 3.
That is true for all kinds of communication equipment. After a day on there is no warming-up, and stability of this receiver is now the best of the lot.
Yaesu FRV, Yaesu FRV VHF Converter for FRG
Another is 1Fthis receiver is made in June A change for 4x 1N or another bridge rectifier manula also possible. The OM who worked on this receiver was clearly not qualified to work at this kind of equipment, and has a BIG soldering iron… After reinserting the board, I had now signals at all bands.
Set the band switch at the 5 Mhz band and adjust T for a reading of 7. Dial lamps are long lasting, but they have to be changed now and then. The AM Led was checked, and was changed because it seemed at the end of his lifespan.
Yaesu FRG-7700 Instruction Manual
Be carefully with the coil cores of the PLL, they have been stabilized by a lot of wax, which can give some trouble. Removing the paint altogether from the sides is also a possibility, it can be done with thinner and rubbing with an old cloth, you have just to be careful with the front itself, the paint there is quick damaged. I tried it, but was not happy with the look of it, It was no Frog anymore, so I put the filter back. First of all I tested the transformer, after cutting off the burned wires and repairing them with the use of crimping tube and suitable wires.
I did only the listed mods on the receiver board, there are some more on the power supply, but i did not use them, so look at the site eventually. The receiver is very sensitive and stable, and has a pleasant audio. The Xtal oscillator was working and at the good frequency.
One of the things I missed on this receivers is a small RIT control or fine tuning, a very handy device when I am listening in on a net or rag chewing Hams. Remove the power cord first!! Kenwood used the same IC in their R receiver, so that can be a source as well.
The displayed frequency is the PLL frequency 0. By submitting a comment, you are declaring that you agree with these rules: