Four channel tone filter radio
08-22-2012, 02:55 PM
#1
Thread Starter
Four channel tone filter radio
For who is interested in radios.
Transmitter of the period 1966, 27 Mc four channel,.picture 1, scratch built AM double simultaneous, so two tone generators. Circuit design was of Helmut Bruss, Germany!.
The receiver is "new", finished these days, superregen and equiped with 4 tonefilters (Circuit design Schumacher, Germany) to control 2 servos. Total weigh 150 gram! The old receivers did evaporate in time. The relais are "modified", from an old microwave oven.
Photograph 3 inside the transmitter. The case is designed to "store" 3 4.5 V batteries for 13.5 VDC. Currents draw 40 a 50 mA. Max current for the PA transistor, 30 mA!. All the brown sheet is "Pertinax" also the printed circuit boards..
Picture 4., amplitude modulation shown when one of the tones is activated. 1000 - 5000 Hz is used for tone filters.
In the future the plane will be rebuilt. Photograph 5 is with the 2 channel and photograph 6 with the 3 channel.
Now 4 channels! What a luxury! Hanna is proud too!! She always shows up with the result of a project, the QA employee.
TF
Transmitter of the period 1966, 27 Mc four channel,.picture 1, scratch built AM double simultaneous, so two tone generators. Circuit design was of Helmut Bruss, Germany!.
The receiver is "new", finished these days, superregen and equiped with 4 tonefilters (Circuit design Schumacher, Germany) to control 2 servos. Total weigh 150 gram! The old receivers did evaporate in time. The relais are "modified", from an old microwave oven.
Photograph 3 inside the transmitter. The case is designed to "store" 3 4.5 V batteries for 13.5 VDC. Currents draw 40 a 50 mA. Max current for the PA transistor, 30 mA!. All the brown sheet is "Pertinax" also the printed circuit boards..
Picture 4., amplitude modulation shown when one of the tones is activated. 1000 - 5000 Hz is used for tone filters.
In the future the plane will be rebuilt. Photograph 5 is with the 2 channel and photograph 6 with the 3 channel.
Now 4 channels! What a luxury! Hanna is proud too!! She always shows up with the result of a project, the QA employee.
TF
08-26-2012, 07:30 AM
#5
Thread Starter
RE: Four channel tone filter radio
Four channels so two servos needed
I still do have my Metz (Germany) two channel servo of the past so a second was needed to complete the 4 channel, two servo radio.
My choise was the Simprop Contest (analog) proportional servo converted for 2 tone filters. (Back io the future!). The limit- and neutralizing switches are mounted on the place of the potentiometer. Speed is reduced by a resistor.
Some details to make the servo reliable, wiring etc, but he will do the job.
Neutralizing is done by energizing the (second) tonefilters, Profit, only four wires are needed to couple the servo with the receiver. No tab is needed, the motor is energized by 4,8 VDC.
Video:
http://www.youtube.com/watch?v=bPTAV...ature=youtu.be
TF
I still do have my Metz (Germany) two channel servo of the past so a second was needed to complete the 4 channel, two servo radio.
My choise was the Simprop Contest (analog) proportional servo converted for 2 tone filters. (Back io the future!). The limit- and neutralizing switches are mounted on the place of the potentiometer. Speed is reduced by a resistor.
Some details to make the servo reliable, wiring etc, but he will do the job.
Neutralizing is done by energizing the (second) tonefilters, Profit, only four wires are needed to couple the servo with the receiver. No tab is needed, the motor is energized by 4,8 VDC.
Video:
http://www.youtube.com/watch?v=bPTAV...ature=youtu.be
TF
08-28-2012, 05:30 AM
#6
Thread Starter
RE: Four channel tone filter radio
Fuctional test and visual inspection by the QA employee Hanna.
Coupling of the Metz servo is also functional. Also Metz uses the second tone filter channel to centralize the servo. Centralizing can be switched off for both directions (independend) by selecting switches in the servo.
A piezo element is used the audiolize the tones.
Some finishing still has to be done, thinner wiring, casings, connectors, but that can be done later.
The video:
http://www.youtube.com/watch?v=_-XL7OonnuY&feature=plcp
Taurus Flyer
Coupling of the Metz servo is also functional. Also Metz uses the second tone filter channel to centralize the servo. Centralizing can be switched off for both directions (independend) by selecting switches in the servo.
A piezo element is used the audiolize the tones.
Some finishing still has to be done, thinner wiring, casings, connectors, but that can be done later.
The video:
http://www.youtube.com/watch?v=_-XL7OonnuY&feature=plcp
Taurus Flyer
09-05-2012, 10:45 AM
#7
Thread Starter
RE: Four channel tone filter radio
Because original parts are scarce I did design a second circuit board based on silicon transistors. This circuit board for real practice use is more reliable and serviceable. The old board is for the museum. see second photograph.
"Power" transistor is the "modern" 2N2219A in common emitter configuration instead of the AF118 germanium tranistor in common base.
Both transistors were often used in the past.
Modulation still with a hand made modulation transformer for collector and base mdulation, for the AF118, modulation was collector - emitter.
Result of modulation is visible in photograph 4. There is also is also more power available.
To do, mounting a heat sink!
TF
"Power" transistor is the "modern" 2N2219A in common emitter configuration instead of the AF118 germanium tranistor in common base.
Both transistors were often used in the past.
Modulation still with a hand made modulation transformer for collector and base mdulation, for the AF118, modulation was collector - emitter.
Result of modulation is visible in photograph 4. There is also is also more power available.
To do, mounting a heat sink!
TF
09-10-2012, 01:56 PM
#8
Thread Starter
RE: Four channel tone filter radio
Double simultaneous?
For who is interested in radio systems.
An important part of the (super regenerative) receiver is the detector of the receiver combined with the right filtering.
The detector, combined with that right filtering does show us the tones of the transmitter, also the combined, two tones is needed, of a double symultaneous transmitter.
The outputsignal of such a combination of tones is shown in photograph three.
Signals are the down elevator and the right rudder signals which are separate shown in photographs one and two.
When the shape of the signal is right both relais of tone filters are activated, in this case, to have right rudder and down elevator.
Of course all combinations of rudder and elevator are needed (4) and possible.
A German system also is to alternate the both tones a few times each second. With such a system more modulation dept is adjustable combined with higher level of sensitivity of the receiver filters, which can result in an expanded range.
A second trick is, electronic cross linking of the tonefilters of each servo. The activated filter (relais) blocks his "partner" filter electronically.
TF
For who is interested in radio systems.
An important part of the (super regenerative) receiver is the detector of the receiver combined with the right filtering.
The detector, combined with that right filtering does show us the tones of the transmitter, also the combined, two tones is needed, of a double symultaneous transmitter.
The outputsignal of such a combination of tones is shown in photograph three.
Signals are the down elevator and the right rudder signals which are separate shown in photographs one and two.
When the shape of the signal is right both relais of tone filters are activated, in this case, to have right rudder and down elevator.
Of course all combinations of rudder and elevator are needed (4) and possible.
A German system also is to alternate the both tones a few times each second. With such a system more modulation dept is adjustable combined with higher level of sensitivity of the receiver filters, which can result in an expanded range.
A second trick is, electronic cross linking of the tonefilters of each servo. The activated filter (relais) blocks his "partner" filter electronically.
TF
09-16-2012, 02:40 PM
#9
Thread Starter
RE: Four channel tone filter radio
A small update for who is interested (FWII).
I decided to modify two more servos, Simprop Tiny servos, for my system.
When something happen during a flight it can be the end of the Metz servo of post 5 and that servo is too valuable to loose. I did my first radio controlled glider attempts with that servo and later used it in my first motor plane.
The Simprop Tiny servo's are provided with switches, no slide contacts, activated by a curved wheel cut from the original potentiometer slide contact.
Weight of the radio and servos is 233 grams now. The battery of four penlights will add another 133 grams so it will be 366 grm for the cargo lifter.
All is working well now.
Next activity is field testing to adjust the tone filters and measure the range.
Taurus Tone Flyer
I decided to modify two more servos, Simprop Tiny servos, for my system.
When something happen during a flight it can be the end of the Metz servo of post 5 and that servo is too valuable to loose. I did my first radio controlled glider attempts with that servo and later used it in my first motor plane.
The Simprop Tiny servo's are provided with switches, no slide contacts, activated by a curved wheel cut from the original potentiometer slide contact.
Weight of the radio and servos is 233 grams now. The battery of four penlights will add another 133 grams so it will be 366 grm for the cargo lifter.
All is working well now.
Next activity is field testing to adjust the tone filters and measure the range.
Taurus Tone Flyer
09-19-2012, 02:08 PM
#10
RE: Four channel tone filter radio
This is a brave and interesting revival.
Would it not have been simpler to use Bellamatics for servos?
They would not need to be modified, and the Simprop servos would not have been "sacrificed".
Would it not have been simpler to use Bellamatics for servos?
They would not need to be modified, and the Simprop servos would not have been "sacrificed".
09-19-2012, 03:47 PM
#11
Thread Starter
RE: Four channel tone filter radio
JMP, hello, thanks for the compliment!
About the Tiny''s, Keyword and slogan of the project is, "Cheap, low budget, just the way I started".BTW recycling I have always done in my hobby and is an important part of scratch building!
The Tiny servo's are given to me by a collegue model pilot and are in fact written off. Also the history is unknown and for that reason it wouldn't be wise to use these again or sell them, I did check the electrical motors and gearboxes and these are in good condition. For me these servos are reliable now to use again is this confuguration. I have about 3 more of these for spare parts and service!
A photograph of the completed wiring with connectors, made of male and female 5 pin DIN plugs is added to this post now,
Still important activity to do is the range check.
A video will be made of the set showing the servos simultaneous functioning.
More to show,
Taurus Flyer.
About the Tiny''s, Keyword and slogan of the project is, "Cheap, low budget, just the way I started".BTW recycling I have always done in my hobby and is an important part of scratch building!
The Tiny servo's are given to me by a collegue model pilot and are in fact written off. Also the history is unknown and for that reason it wouldn't be wise to use these again or sell them, I did check the electrical motors and gearboxes and these are in good condition. For me these servos are reliable now to use again is this confuguration. I have about 3 more of these for spare parts and service!
A photograph of the completed wiring with connectors, made of male and female 5 pin DIN plugs is added to this post now,
Still important activity to do is the range check.
A video will be made of the set showing the servos simultaneous functioning.
More to show,
Taurus Flyer.
09-20-2012, 11:21 AM
#12
Thread Starter
RE: Four channel tone filter radio
Range check done and alright.
Retracted antenna, distance more than 100 m.
Normal antenna length, distance was 857 m. This test was limited by local circumstances, privat property. At that position I was standing between cornfields, the corn much taller than I am.
Second (back-up) check was 613 m of which location I show a photograph.
These distances are shown on Google Earth.
The four channels were stil all controllable at these distances but also at one meter, also simultaneously, so the set seems to be useable to fly. Fine tuning of the tone filters wasn't needed either.
During the tests we used a "TopCom Twintalker 3000" set near transmitter and receiver without any negative influence! (0,5 Watt - 446 MHz). Visible contact wasn't possible.
Measuring the max distance is possible in winter but not really needed. Normally we count with twice these measured distance for flying so that will be at least 17oo m.
Taurus Flyer
Retracted antenna, distance more than 100 m.
Normal antenna length, distance was 857 m. This test was limited by local circumstances, privat property. At that position I was standing between cornfields, the corn much taller than I am.
Second (back-up) check was 613 m of which location I show a photograph.
These distances are shown on Google Earth.
The four channels were stil all controllable at these distances but also at one meter, also simultaneously, so the set seems to be useable to fly. Fine tuning of the tone filters wasn't needed either.
During the tests we used a "TopCom Twintalker 3000" set near transmitter and receiver without any negative influence! (0,5 Watt - 446 MHz). Visible contact wasn't possible.
Measuring the max distance is possible in winter but not really needed. Normally we count with twice these measured distance for flying so that will be at least 17oo m.
Taurus Flyer
09-22-2012, 12:40 PM
#13
Thread Starter
RE: Four channel tone filter radio
10-01-2012, 09:39 AM
#14
Thread Starter
RE: Four channel tone filter radio
TXPERIMENTAL
Preparing the next stage of the project, a scratch built tube transmitter, 4 channel.
See photograph 1.
The transmitter is given to me and after a study of the internals I decided to rebuild this. The oscillator is also transmitter and the second part of the tube (DCC90) is used for the single tone generator. Not the way I prefer the circuit. So there will be added one (or two) transistorized tone generator(s) and the tube will by used for RF, oscillator and amplifier.
First of all I needed a converter to generate the 100 VDC to replace the empty battery, so a scratch built converter is in style of the projet. The dimensions of the converter are choosen so I can fit it in the original battery included 10 AA cells.
A filament battery still can be used the normal way, but, also possible to add 4 AA cells in the BEREC B1643
T.F.
Preparing the next stage of the project, a scratch built tube transmitter, 4 channel.
See photograph 1.
The transmitter is given to me and after a study of the internals I decided to rebuild this. The oscillator is also transmitter and the second part of the tube (DCC90) is used for the single tone generator. Not the way I prefer the circuit. So there will be added one (or two) transistorized tone generator(s) and the tube will by used for RF, oscillator and amplifier.
First of all I needed a converter to generate the 100 VDC to replace the empty battery, so a scratch built converter is in style of the projet. The dimensions of the converter are choosen so I can fit it in the original battery included 10 AA cells.
A filament battery still can be used the normal way, but, also possible to add 4 AA cells in the BEREC B1643
T.F.
10-05-2012, 02:15 PM
#16
Thread Starter
RE: Four channel tone filter radio
So,
Batteries for the filament aren't needed anymore for the new MOPA, the master oscillator and power amplifier. The whole circuit board can be placed in the casing of the original scratch built tube radio.
I didn't see this before but it was worth to try. There are tubes that need 12.6 V filament tension, so, when supplying my convertor with 12 VDC why not use such a radiotube , double triode, with that kind of filament for 12 VDC??
On the photograph is shown all what is needed to make the carriër wave, only needed a 12 V battery to supply and the transistor tone generator (,or two of these).
All small components are mounted on bottom site of the board, capacitors, chokes, resistors.
The efficiëncy of the converter is +80 %, so for 10 mA at 100 VDC a current of 100 mA of the battery is needed, added the current needed for heating of the tube,(filament) 150 mA, makes 250 mA, the grid modulation of the PA (?) is efficiënt and together with the tone generator another 10 mA is needed, makes total 260 mA. at 12 VDC.
BTW this tube was not designed for supply by a battery but for me it does a good job! It looks like 100 VDC is enough for the needed output power but, If I want I can go to 300VDC with this tube.
TF.
Batteries for the filament aren't needed anymore for the new MOPA, the master oscillator and power amplifier. The whole circuit board can be placed in the casing of the original scratch built tube radio.
I didn't see this before but it was worth to try. There are tubes that need 12.6 V filament tension, so, when supplying my convertor with 12 VDC why not use such a radiotube , double triode, with that kind of filament for 12 VDC??
On the photograph is shown all what is needed to make the carriër wave, only needed a 12 V battery to supply and the transistor tone generator (,or two of these).
All small components are mounted on bottom site of the board, capacitors, chokes, resistors.
The efficiëncy of the converter is +80 %, so for 10 mA at 100 VDC a current of 100 mA of the battery is needed, added the current needed for heating of the tube,(filament) 150 mA, makes 250 mA, the grid modulation of the PA (?) is efficiënt and together with the tone generator another 10 mA is needed, makes total 260 mA. at 12 VDC.
BTW this tube was not designed for supply by a battery but for me it does a good job! It looks like 100 VDC is enough for the needed output power but, If I want I can go to 300VDC with this tube.
TF.
10-10-2012, 11:58 AM
#17
Thread Starter
RE: Four channel tone filter radio
And so the circuit board looks like with one tone generator.
There are locations to mount capacitors for 6 channels, six tones.
I changed the RF oscillator from 'tuned plate tuned grid' (TPTG) in a Hartley oscillator for better efficiency, more power for same money.
The LC (coil /capacitor) sinus tone generator is a proven design of the past. I modified it slightly so I can use one generator over the whole tone range with equal amplitude for each channel by only changing capacitors. All components and connections are mounted on bottom side of the board as was often seen in the past.
Still to do,
Making the two 2 channel sticks and the casing.
TF
There are locations to mount capacitors for 6 channels, six tones.
I changed the RF oscillator from 'tuned plate tuned grid' (TPTG) in a Hartley oscillator for better efficiency, more power for same money.
The LC (coil /capacitor) sinus tone generator is a proven design of the past. I modified it slightly so I can use one generator over the whole tone range with equal amplitude for each channel by only changing capacitors. All components and connections are mounted on bottom side of the board as was often seen in the past.
Still to do,
Making the two 2 channel sticks and the casing.
TF
10-11-2012, 02:27 PM
#18
Thread Starter
RE: Four channel tone filter radio
And the two , two channel sticks nearly finished.
Main function of these sticks, convert the pilots input in binairy electrical signales (pulses) for the tone generator of the transmitter. Yesss....... this is the future, no more analog sticks with these unreliable potentiometers, but digital in the first step of the control loop to command the model!!!.
Sources:
Microswitches, discarded microwave ovens.
threaded bushes, discarded lamp armature
Shafts, steel nails
Sticks, made of a shaft of an discarded old printer.
Sheet metal, of an old supply casing
The little shaft is pressed in the stick. Pivots (greased of course!) are positioned in the threaded bushes.
The mechanic will be mounted with the central bush and nut in front panel of the casing of the transmitter so,
Next activity the casing.
Can take some time because there are some other, more important (?), activities to do in the first place.
TF
Main function of these sticks, convert the pilots input in binairy electrical signales (pulses) for the tone generator of the transmitter. Yesss....... this is the future, no more analog sticks with these unreliable potentiometers, but digital in the first step of the control loop to command the model!!!.
Sources:
Microswitches, discarded microwave ovens.
threaded bushes, discarded lamp armature
Shafts, steel nails
Sticks, made of a shaft of an discarded old printer.
Sheet metal, of an old supply casing
The little shaft is pressed in the stick. Pivots (greased of course!) are positioned in the threaded bushes.
The mechanic will be mounted with the central bush and nut in front panel of the casing of the transmitter so,
Next activity the casing.
Can take some time because there are some other, more important (?), activities to do in the first place.
TF
10-14-2012, 03:30 PM
#19
Thread Starter
RE: Four channel tone filter radio
For tone modulation of this (tube) Hartley Oscillator and Power Amplifier I use grid modulation.
For grid modulation a minimum of modulator power is desired and also a (power?) transformator isn’t needed as shown in post 7 of this thread. Grid modulation was widely used in portable and mobile equipment to reduce size and power requirements. A problem of the method can be linearity but results are very promising on this moment.
The photograph does show a modulation depth of 50 %, so I have to adjust some more gain for the modulator amplifier but there is room for that and is part of the final adjustment after mounting the board in the casing. Supply voltage of the modulator amplifier is 12 VDC and that seems to be enough to have the right modulation depth.
Casing is on his way, currently on the drawing board.
TF
For grid modulation a minimum of modulator power is desired and also a (power?) transformator isn’t needed as shown in post 7 of this thread. Grid modulation was widely used in portable and mobile equipment to reduce size and power requirements. A problem of the method can be linearity but results are very promising on this moment.
The photograph does show a modulation depth of 50 %, so I have to adjust some more gain for the modulator amplifier but there is room for that and is part of the final adjustment after mounting the board in the casing. Supply voltage of the modulator amplifier is 12 VDC and that seems to be enough to have the right modulation depth.
Casing is on his way, currently on the drawing board.
TF
10-18-2012, 06:20 AM
#20
Thread Starter
RE: Four channel tone filter radio
The casing is "under construction".
Wood, birch plywood.
A second layer of plywood will be attached to the visible to create enough rigidity, so totall thickness will be 6 mm/ 1/4 inch.
Inside I'll mount brass shielding on the "walls".
The dimensions are based on minimum content for the electronics, the circuit board, 3 sticks and on/off switch and to supply, two dummy B1643 90 V battery's and (dummy) 2 D mono cells of 1.5 V.
Sticks will be mounted on front of the casing and the entrance on the backside.
TF
Wood, birch plywood.
A second layer of plywood will be attached to the visible to create enough rigidity, so totall thickness will be 6 mm/ 1/4 inch.
Inside I'll mount brass shielding on the "walls".
The dimensions are based on minimum content for the electronics, the circuit board, 3 sticks and on/off switch and to supply, two dummy B1643 90 V battery's and (dummy) 2 D mono cells of 1.5 V.
Sticks will be mounted on front of the casing and the entrance on the backside.
TF
10-21-2012, 09:00 AM
#22
Thread Starter
RE: Four channel tone filter radio
Mounting of the components is finished so installing of the wiring is the next activity.
The transmitter will be wired as a four channel radio but provisions are already made to expand to 6 channel.
Location of the added stick in the future, above the filament cells.
The attentive reader of course will detect the special Kalimba setting of the main sticks, this is an own development to speed up the pilots operating input.
TF
The transmitter will be wired as a four channel radio but provisions are already made to expand to 6 channel.
Location of the added stick in the future, above the filament cells.
The attentive reader of course will detect the special Kalimba setting of the main sticks, this is an own development to speed up the pilots operating input.
TF
10-22-2012, 08:59 AM
#23
RE: Four channel tone filter radio
The attentive reader of course will detect the special Kalimba setting of the main sticks, this is an own development to speed up the pilots operating input.
10-22-2012, 10:28 AM
#24
Thread Starter
RE: Four channel tone filter radio
JMP, hello,
Yes designing is fun and the result, we have our custom built Special. No, for me no galloping ghost, I cannot combine that methode with control of gliders. Too much waste of energy such a fish tail on a bird. So “bang bang” for me in this period.
Your pink transmitter is a beauty and the color makes is a real wolf in sheep's clothes. Is that galloping ghost too, the pink? Winning the game with such a radio must (have) be(en) a pleasure, bravo.
My goal for this radio is participating in fun meetings in the future, that's why I need some kind of motor control, maybe three position.
Weakest link in the control loop of "bang bang" radio control (Dutch 'tip tip'), we all know, is speed of the thumbs, so I adopted a part of the design and playing technique of the African Kalimba. Why inventing the wheel?
Clou of the trick, not needed anymore is bending my thumbs, only swing, to manipulate the sticks. With this method it's possible to have a high cycle rate, that's why I call it "SUPERREGEN FAST".
The future will show me if a radio with this stick setting is a better system than proportional in general, if so, than it was a missed change 50 years ago. If not? It will improve my Kalimba playing.(LOL)
And galloping ghost? Not yet, maybe when I am older and my thumbs need some retirement.
BTW, I copied my Kalimba of a real original African instrument owned by my accordeon teacher, the reeds are original of the gutters of Edinburgh, Scotland because the Dutch reeds are too thin.
American Reeds I am also familiar with, the brand of the harmonium we owned in the past!
So Kalimba, not only use the technique but also the instrument to practise, it’s my flight s(t)imulator.
and maybe one reed on front of the transmitter for the motor control, ........poing ....... poing
Have fun,
TF
Yes designing is fun and the result, we have our custom built Special. No, for me no galloping ghost, I cannot combine that methode with control of gliders. Too much waste of energy such a fish tail on a bird. So “bang bang” for me in this period.
Your pink transmitter is a beauty and the color makes is a real wolf in sheep's clothes. Is that galloping ghost too, the pink? Winning the game with such a radio must (have) be(en) a pleasure, bravo.
My goal for this radio is participating in fun meetings in the future, that's why I need some kind of motor control, maybe three position.
Weakest link in the control loop of "bang bang" radio control (Dutch 'tip tip'), we all know, is speed of the thumbs, so I adopted a part of the design and playing technique of the African Kalimba. Why inventing the wheel?
Clou of the trick, not needed anymore is bending my thumbs, only swing, to manipulate the sticks. With this method it's possible to have a high cycle rate, that's why I call it "SUPERREGEN FAST".
The future will show me if a radio with this stick setting is a better system than proportional in general, if so, than it was a missed change 50 years ago. If not? It will improve my Kalimba playing.(LOL)
And galloping ghost? Not yet, maybe when I am older and my thumbs need some retirement.
BTW, I copied my Kalimba of a real original African instrument owned by my accordeon teacher, the reeds are original of the gutters of Edinburgh, Scotland because the Dutch reeds are too thin.
American Reeds I am also familiar with, the brand of the harmonium we owned in the past!
So Kalimba, not only use the technique but also the instrument to practise, it’s my flight s(t)imulator.
and maybe one reed on front of the transmitter for the motor control, ........poing ....... poing
Have fun,
TF
10-27-2012, 02:38 PM
#25
Thread Starter
RE: Four channel tone filter radio
Adjusting the modulation depth takes more time than expected but,,,,, no problem, scratch building is the most interesting way of modeling, the learning curve
As result of the high power level of the oscillator I have to pre adjust the control grid of the triode amplifier and create a high voltage modulation amplifier to have 100 % depth . In such a period I cannot make a nice photograph of the circuit, components all over the board, see the photograph 1, but at least I show you a nice background.
I want the 100 % depth for the future, when adding a second tone generator and use them simultaneously. For one generator 50 % depth will do.
Why that second generator in the future?
When the radio is finally finished I also want to control my replica of the first successfull Taurus of Ed Kazmirski, see photograph 2. and then I need an expansion of the transmitter to 8 channel double simultaneous.
When the radio is finally finished?
I am afraid it will never be, but a never ending story. Of course you also can buy a radio and/or a plane, there is a lot debating about that but for me my way of doing these things is Old School and the way I like it most.
TF
As result of the high power level of the oscillator I have to pre adjust the control grid of the triode amplifier and create a high voltage modulation amplifier to have 100 % depth . In such a period I cannot make a nice photograph of the circuit, components all over the board, see the photograph 1, but at least I show you a nice background.
I want the 100 % depth for the future, when adding a second tone generator and use them simultaneously. For one generator 50 % depth will do.
Why that second generator in the future?
When the radio is finally finished I also want to control my replica of the first successfull Taurus of Ed Kazmirski, see photograph 2. and then I need an expansion of the transmitter to 8 channel double simultaneous.
When the radio is finally finished?
I am afraid it will never be, but a never ending story. Of course you also can buy a radio and/or a plane, there is a lot debating about that but for me my way of doing these things is Old School and the way I like it most.
TF