Home |
Search |
Today's Posts |
#1
![]() |
|||
|
|||
![]() Rick Disney wrote: Greetings , Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center tuner only adds 500 hz...Navy Mars operates at 4470.5. ..Any help? Easiest would be to move the 3.5 - 4.0 band up to say 4.2 - 4.7, but you would have to sacrifice the original band. You might be able to switch components the "pad" the existing components in and out to get both the ham band and Mars. Start with getting the manual and schematic from: http://bama.sbc.edu/heath.htm Examine the schematic and rig to determine which coils/capacitors are switched in for the 80 and 40 meter bands. You'll see that the circuit is the same for each band, but the values of the components are different. Remember to do this both for the transmitter and receiver portions of the transceiver. Once you have a firm understanding of how Heath switches from one band to the other, you will be able to "functionally" design (specify what components to use, and where they need to go in the circuit, but no component values determined yet) for your new band, which should start at something like 4.2 or 4.3 mHz. The manual probably has a theory of operations or circuit description section which will help you to understand those circuits. Next, you establish component values that will make your new circuit work at the design frequency - 4.2 or 4.3 mHz. Next, determine how you can incorporate the new components into the rig. Are you willing to give up the 3.5 - 4.0 range, or any other band? Can you add a switch to switch in new components, such that you don't have to give up any existing band? Essentially, you need to figure out whether major surgery is required, and whether you are willing to do it. 73's Rick KAØDIZ |
#2
![]() |
|||
|
|||
![]() Rick Disney wrote: Greetings , Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center tuner only adds 500 hz...Navy Mars operates at 4470.5. ..Any help? Easiest would be to move the 3.5 - 4.0 band up to say 4.2 - 4.7, but you would have to sacrifice the original band. You might be able to switch components the "pad" the existing components in and out to get both the ham band and Mars. Start with getting the manual and schematic from: http://bama.sbc.edu/heath.htm Examine the schematic and rig to determine which coils/capacitors are switched in for the 80 and 40 meter bands. You'll see that the circuit is the same for each band, but the values of the components are different. Remember to do this both for the transmitter and receiver portions of the transceiver. Once you have a firm understanding of how Heath switches from one band to the other, you will be able to "functionally" design (specify what components to use, and where they need to go in the circuit, but no component values determined yet) for your new band, which should start at something like 4.2 or 4.3 mHz. The manual probably has a theory of operations or circuit description section which will help you to understand those circuits. Next, you establish component values that will make your new circuit work at the design frequency - 4.2 or 4.3 mHz. Next, determine how you can incorporate the new components into the rig. Are you willing to give up the 3.5 - 4.0 range, or any other band? Can you add a switch to switch in new components, such that you don't have to give up any existing band? Essentially, you need to figure out whether major surgery is required, and whether you are willing to do it. 73's Rick KAØDIZ |
#3
![]() |
|||
|
|||
![]()
In article , Rick Disney
says... Greetings , Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center tuner only adds 500 hz...Navy Mars operates at 4470.5. ..Any help? I've not had experience with that specific radio, but... assuming it's a simple VFO, it should be a simple matter to tweak coil(s), capacitor(s), or both to bring the low end up a bit. If you're going to tweak coils, I suggest using a grid dip meter to find a good spot. You should probably get hold of the manual for the unit first. Do a google search for 'W7FG vintage manuals.' Good hunting. -- Dr. Anton Squeegee, Director, Dutch Surrealist Plumbing Institute (Known to some as Bruce Lane, KC7GR) kyrrin a/t bluefeathertech d-o=t c&o&m "Quando Omni Flunkus Moritati" (Red Green) |
#4
![]() |
|||
|
|||
![]()
In article , Rick Disney
says... Greetings , Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center tuner only adds 500 hz...Navy Mars operates at 4470.5. ..Any help? I've not had experience with that specific radio, but... assuming it's a simple VFO, it should be a simple matter to tweak coil(s), capacitor(s), or both to bring the low end up a bit. If you're going to tweak coils, I suggest using a grid dip meter to find a good spot. You should probably get hold of the manual for the unit first. Do a google search for 'W7FG vintage manuals.' Good hunting. -- Dr. Anton Squeegee, Director, Dutch Surrealist Plumbing Institute (Known to some as Bruce Lane, KC7GR) kyrrin a/t bluefeathertech d-o=t c&o&m "Quando Omni Flunkus Moritati" (Red Green) |
#5
![]() |
|||
|
|||
![]()
Rick Disney wrote:
Greetings , Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center tuner only adds 500 hz...Navy Mars operates at 4470.5. ..Any help? 73's Rick KAØDIZ Each band has a crystal oscillator that sets the band of frequencies. Change that crystal to a different one that will cover the frequency you want. Bill K7NOM |
#6
![]() |
|||
|
|||
![]()
Rick Disney wrote:
Greetings , Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center tuner only adds 500 hz...Navy Mars operates at 4470.5. ..Any help? 73's Rick KAØDIZ Each band has a crystal oscillator that sets the band of frequencies. Change that crystal to a different one that will cover the frequency you want. Bill K7NOM |
#7
![]() |
|||
|
|||
![]()
"Rick Disney" wrote in message
... Greetings , Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center tuner only adds 500 hz...Navy Mars operates at 4470.5. ..Any help? 73's Rick KAØDIZ Rick - I would also suggest that you review the article "Optimizing the Heathkit HW-101" by Mark Graalman WB8JKR (Adobe Acrobat) http://members.tripod.com/NRWILLIAMSON/Hw101.pdf Photo http://oak.cats.ohiou.edu/~postr/bapix/HW101.html Improving the HW-101 http://www.fvh.accessus.net/~dwentz/...ray_k4jpn.html Partial manual and schematic (BAMA) http://bama.sbc.edu/heath.htm g. beat w9gb |
#8
![]() |
|||
|
|||
![]() "Rick Disney" wrote in message ... Greetings , Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center tuner only adds 500 hz...Navy Mars operates at 4470.5. ..Any help? 73's Rick KAØDIZ ..... I forgot the service bulletins http://www.qsl.net/kb7rgg/heath/Serv...s/sb-hw101.doc w9gb |
#9
![]() |
|||
|
|||
![]()
"Rick Disney" wrote in message
... Greetings , Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center tuner only adds 500 hz...Navy Mars operates at 4470.5. ..Any help? 73's Rick KAØDIZ Rick - I would also suggest that you review the article "Optimizing the Heathkit HW-101" by Mark Graalman WB8JKR (Adobe Acrobat) http://members.tripod.com/NRWILLIAMSON/Hw101.pdf Photo http://oak.cats.ohiou.edu/~postr/bapix/HW101.html Improving the HW-101 http://www.fvh.accessus.net/~dwentz/...ray_k4jpn.html Partial manual and schematic (BAMA) http://bama.sbc.edu/heath.htm g. beat w9gb |
#10
![]() |
|||
|
|||
![]() "Rick Disney" wrote in message ... Greetings , Got my hands on a Heathkit HW-101..It's low preset is 3.5 and the center tuner only adds 500 hz...Navy Mars operates at 4470.5. ..Any help? 73's Rick KAØDIZ ..... I forgot the service bulletins http://www.qsl.net/kb7rgg/heath/Serv...s/sb-hw101.doc w9gb |
Reply |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Attention MARS & ex MARS Operators | Equipment | |||
Attention MARS & ex MARS Operators | Equipment | |||
Attention MARS & Ex MARS Operators | Dx | |||
Attention MARS & Ex MARS Operators | Dx | |||
Attention MARS & ex MARS Operators | Boatanchors |