Falcon and RoadRunner Review Analog Planet
Just came across this partial review on Analog Planet. A full review of the Falcon and RoadRunner is planned for later....Analog Planet
Just came across this partial review on Analog Planet. A full review of the Falcon and RoadRunner is planned for later....Analog Planet
) it will.
I believe we have sold them onto Systemdek turntables. I know they use an AC synch motor (which is one of the requirements). If the MH Cruise Control (3W) works with it, the Falcon will definitely work (5W).
We get asked this question more than any other. The best advice I can give, is to look at the motor for a power rating (either W or VA). We will work with any AC synchronous motor of 5W or less. We output 115VAC, but can drive lower voltage motors by plugging the motor's wall adapter into our output.
We get asked this question more than any other. The best advice I can give, is to look at the motor for a power rating (either W or VA). We will work with any AC synchronous motor of 5W or less. We output 115VAC, but can drive lower voltage motors by plugging the motor's wall adapter into our output.
Falcon power supply for the Alphason Sonata
Dear Pyramid,
I have a few questions about the Falcon and Roadrunner:
- First, Falcon output power: I have an Alphason Sonata turntable from around 1987. It uses two motors which appear to be the same as the Premotec 31813 motor. I attach the data sheet for this motor, it quotes input power of 1.8 Watt. This appears to be the same motor as that used on the Linn Sondek LP12, Pink Triangle PT TOO, Heybrook TT2 and several other British belt drive turntables from that era.
Given that the maximum output power quoted for the Falcon is 5 Watt, I guess it could it drive two of these 1.8 Watt motors without trouble. But if you happen to have two of these motors to hand, perhaps you could test this and let me know for sure?
- Second, Falcon frequency calibration: the manual states that we can calibrate the offset for each speed in 0.01 rpm increments but it doesn't state a maximum range. Is there a limit to the maximum plus and/or minus speed offset that can be applied for each speed and if so, what is the limit?
- Third, using the Falcon and Roadrunner to set speed: when using the Roadrunner to control the Falcon, according to the manual the speed is set to exactly the nominal speed, and the manual fine speed control does not work. Would it not be possible to make it so that the manual fine speed control does work, and the Roadrunner keeps the speed of the turntable to that set by the user instead of the nominal speed?
- Fourth, 78 rpm: Some of your literature mentions 78 rpm. Does - or can - the Falcon provide 78 rpm in addition to 33 1/3 and 45?
Best regards,
George
Dear Pyramid,
I have a few questions about the Falcon and Roadrunner:
- First, Falcon output power: I have an Alphason Sonata turntable from around 1987. It uses two motors which appear to be the same as the Premotec 31813 motor. I attach the data sheet for this motor, it quotes input power of 1.8 Watt. This appears to be the same motor as that used on the Linn Sondek LP12, Pink Triangle PT TOO, Heybrook TT2 and several other British belt drive turntables from that era.
Given that the maximum output power quoted for the Falcon is 5 Watt, I guess it could it drive two of these 1.8 Watt motors without trouble. But if you happen to have two of these motors to hand, perhaps you could test this and let me know for sure?
- Second, Falcon frequency calibration: the manual states that we can calibrate the offset for each speed in 0.01 rpm increments but it doesn't state a maximum range. Is there a limit to the maximum plus and/or minus speed offset that can be applied for each speed and if so, what is the limit?
- Third, using the Falcon and Roadrunner to set speed: when using the Roadrunner to control the Falcon, according to the manual the speed is set to exactly the nominal speed, and the manual fine speed control does not work. Would it not be possible to make it so that the manual fine speed control does work, and the Roadrunner keeps the speed of the turntable to that set by the user instead of the nominal speed?
- Fourth, 78 rpm: Some of your literature mentions 78 rpm. Does - or can - the Falcon provide 78 rpm in addition to 33 1/3 and 45?
Best regards,
George
The Falcon will work in this application. Our output is 115VAC so the 6.8K series resistor should be removed if this is a 220V system. The 50Hz pulley is front panel selectable.
In calibration mode, the adjustment range is ±1.0 RPM in 0.01 RPM steps. This setting changes the base frequency for each speed and there are separate adjustments for 33, 45 & 78 RPM (if enabled).
When using the RoadRunner tach and the two are connected together, the calibration mode data is overwritten since that is the function of the tach: to precisely control the base frequency of each speed automatically (rather than manually using cal mode). However, the front panel "tempo" control still operates when using the tach (33.5 would maintain a speed of 33.533 RPM). The front panel tempo range is ±1.0 RPM for 33 & 45 modes and ±6.0 RPM for 78 (in 0.1 RPM steps vs 0.01 RPM steps in cal mode).
The Falcon is capable of 78 RPM, but since most users only need 33 & 45, this mode is "hidden" as shipped from the factory. To activate 78 RPM mode, solder jumper J3 is installed. The user will then have all 3 speeds (display will move between 33->45->78->33...).
78 RPM mode requires a standard 50Hz pulley and the belt to be installed on the large spindle. This is the ONLY combination that will work for 78 RPM mode. The output frequencies then become 37Hz, 50Hz and 87.5Hz and the phase capacitor will not be optimum for 33 and 78 RPM. The motor will have higher vibration at 33 RPM than in normal 33/45 RPM only mode and will have less torque at 78 RPM. While we have tested this on several applications, this is a limitation of the motor and using a single phase cap to cover a large range of frequencies.
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Thank you Pyramid for your prompt reply.
Good to know that I'll be able to resurrect my Alphason Sonata. They all came originally with an electronic power supply, so the motors weren't wired to work from 240V mains, they were fed a nominal 115V and they had single-speed pulleys. An on-board two-speed quartz-oscillator supply was standard, this ran directly off the mains. There was also an optional outboard supply called the Atlas. Mine had the on-board supply which eventually blew up.
Is there a way to make the calibration range wider in the positive direction at least, to say +5 rpm? I have, for some time, wanted to try fitting a platter brake to a belt drive turntable, because I feel that would benefit the performance (it would swamp the effect of stylus drag, it would damp the rotational oscillation of the platter on the springiness of the belt, it would force the motor to provide a larger and constant torque rather than a small, varying torque and it would keep the belt tension constant). So extra motor speed would be needed to counteract the platter brake. Of course I realise that I could have a larger pulley made, but trying it with the power supply first would let me more easily determine how much larger a pulley I will need.
So it's the calibration that is disabled when running in tachometer control mode, not the front panel speed control. Thank you for making this clear.
I understand your choice to make a single-phase supply and provide users with a solution which is "plug and play" in most cases. On the other hand, a two-phase supply could be made to provide two phases electronically maintained in quadrature at all frequencies. Have you considered making a two-phase version of the supply for users who can rewire their turntables for this? Or perhaps a "slave" supply that could be added as an upgrade, to provide the second phase?
I will be sending you a private message about ordering a Falcon.
With best regards,
George
Good to know that I'll be able to resurrect my Alphason Sonata. They all came originally with an electronic power supply, so the motors weren't wired to work from 240V mains, they were fed a nominal 115V and they had single-speed pulleys. An on-board two-speed quartz-oscillator supply was standard, this ran directly off the mains. There was also an optional outboard supply called the Atlas. Mine had the on-board supply which eventually blew up.
Is there a way to make the calibration range wider in the positive direction at least, to say +5 rpm? I have, for some time, wanted to try fitting a platter brake to a belt drive turntable, because I feel that would benefit the performance (it would swamp the effect of stylus drag, it would damp the rotational oscillation of the platter on the springiness of the belt, it would force the motor to provide a larger and constant torque rather than a small, varying torque and it would keep the belt tension constant). So extra motor speed would be needed to counteract the platter brake. Of course I realise that I could have a larger pulley made, but trying it with the power supply first would let me more easily determine how much larger a pulley I will need.
So it's the calibration that is disabled when running in tachometer control mode, not the front panel speed control. Thank you for making this clear.
I understand your choice to make a single-phase supply and provide users with a solution which is "plug and play" in most cases. On the other hand, a two-phase supply could be made to provide two phases electronically maintained in quadrature at all frequencies. Have you considered making a two-phase version of the supply for users who can rewire their turntables for this? Or perhaps a "slave" supply that could be added as an upgrade, to provide the second phase?
I will be sending you a private message about ordering a Falcon.
With best regards,
George
George-
If the original pulley is a single spindle, is it only for 33 RPM? In order to get 78 RPM, it would require a 50Hz pulley with the belt on the larger (45 RPM) spindle. 78 RPM is not possible from the small spindle (33 RPM) on either 50Hz or 60Hz pulleys.
Regarding the platter brake, I think it will cause more stability issues than it solves, but you can certainly try it. The main problem I would run into with a calibration mode greater than ±1 RPM is the display. With 3 digits, I can display ±99 steps of 0.01 RPM plus sign (+/-). The drag from the needle is negligible (0.00x RPM usually); if you want to swamp this, small amounts of drag via thicker bearing oil has been used successfully.
Originally, the PSU had dual outputs, but because of its small size, it could not dissipate the additional heat. The slave idea has been suggested before; technically possible, but not really practical at this point (would require additional connectors/cables for the clock reference). The other problem with dual outputs, it requires rewiring the motor and AC connector which would cause compliance issues. The DIY crowd might accept this but the general public wouldn't and on a commercial product it would most likely be illegal.
If the original pulley is a single spindle, is it only for 33 RPM? In order to get 78 RPM, it would require a 50Hz pulley with the belt on the larger (45 RPM) spindle. 78 RPM is not possible from the small spindle (33 RPM) on either 50Hz or 60Hz pulleys.
Regarding the platter brake, I think it will cause more stability issues than it solves, but you can certainly try it. The main problem I would run into with a calibration mode greater than ±1 RPM is the display. With 3 digits, I can display ±99 steps of 0.01 RPM plus sign (+/-). The drag from the needle is negligible (0.00x RPM usually); if you want to swamp this, small amounts of drag via thicker bearing oil has been used successfully.
Originally, the PSU had dual outputs, but because of its small size, it could not dissipate the additional heat. The slave idea has been suggested before; technically possible, but not really practical at this point (would require additional connectors/cables for the clock reference). The other problem with dual outputs, it requires rewiring the motor and AC connector which would cause compliance issues. The DIY crowd might accept this but the general public wouldn't and on a commercial product it would most likely be illegal.
Hi Pyramid,
Thank you for your answers to my queries.
I have ordered the Falcon and am looking forward to trying it with both my Alphason Sonata and my Heybrook TT2 which has the same Philips / Airpax / Premotec motor.
The Sonata came as standard with an electronic 50Hz / 67.5Hz power supply and 50Hz 33 1/3rpm pulleys on its two motors. Unfortunately it's impossible to use two-step pulleys on a Sonata because of the way it's made. This is probably why the electronic supply was standard.
The TT2 came as standard with a two-step 33 1/3 - 45rpm pulley and direct mains power. Unfortunately mine is the factory upgrade with, again, a 50Hz / 67.5Hz electronic supply (which, like the similar supply in my Sonata, is now dead) and it only has a 50Hz 33 1/3rpm pulley. To get 78rpm, perhaps I can source the two-step pulley, or have one made.
I am curious, did you decide to use the 45 rpm spindle to get 78 rpm because these synchronous motors do not generate sufficient torque at 117Hz or 140.4Hz, or was it for some other reason?
Best regards,
George
Thank you for your answers to my queries.
I have ordered the Falcon and am looking forward to trying it with both my Alphason Sonata and my Heybrook TT2 which has the same Philips / Airpax / Premotec motor.
The Sonata came as standard with an electronic 50Hz / 67.5Hz power supply and 50Hz 33 1/3rpm pulleys on its two motors. Unfortunately it's impossible to use two-step pulleys on a Sonata because of the way it's made. This is probably why the electronic supply was standard.
The TT2 came as standard with a two-step 33 1/3 - 45rpm pulley and direct mains power. Unfortunately mine is the factory upgrade with, again, a 50Hz / 67.5Hz electronic supply (which, like the similar supply in my Sonata, is now dead) and it only has a 50Hz 33 1/3rpm pulley. To get 78rpm, perhaps I can source the two-step pulley, or have one made.
I am curious, did you decide to use the 45 rpm spindle to get 78 rpm because these synchronous motors do not generate sufficient torque at 117Hz or 140.4Hz, or was it for some other reason?
Best regards,
George
You're good at math I see! At 117Hz the motor will not spin, even with manual assistance and even if fed with 90° dual phase outputs. Didn't even try 140 Hz. With 60Hz pulley large spindle the frequency is 104Hz, same problem. 86.7Hz is pushing the limit as the higher the frequency, the lower the torque. Fortunately, we ramp the speed so the motor starts at ~30Hz and evenly ramps up over several seconds.
Since you have 50Hz small spindle only, I will pre-configure the PSU to work with this pulley (33/45 RPM only). I will include instructions for enabling 78 RPM mode if you find a suitable pulley.
Thank you for your order and the very good questions.
Made another minor change to the Falcon PSU firmware:
We do a "Soft Start" to prevent burn-out on the belt at start up; when directly powering the motor from 115VAC, it was no problem to start at 36Hz (~20 RPM) and ramp up to 33 or 45 RPM.
However, if connected to a low voltage motor through a wall adapter, the step down xfmr doesn't much care for 36Hz. The new firmware eliminates the low frequency start up when solder jumper J1 is installed, for use with step down xfmrs. In this case (J1 installed) the PSU will start at 33 RPM (60 Hz); if start up is in 45 RPM mode, the PSU will still start at 33 and ramp to 45 (81 Hz).
We do a "Soft Start" to prevent burn-out on the belt at start up; when directly powering the motor from 115VAC, it was no problem to start at 36Hz (~20 RPM) and ramp up to 33 or 45 RPM.
However, if connected to a low voltage motor through a wall adapter, the step down xfmr doesn't much care for 36Hz. The new firmware eliminates the low frequency start up when solder jumper J1 is installed, for use with step down xfmrs. In this case (J1 installed) the PSU will start at 33 RPM (60 Hz); if start up is in 45 RPM mode, the PSU will still start at 33 and ramp to 45 (81 Hz).
Falcon / RoadRunner Review
Michael Fremer just posted his review of the Falcon PSU and RoadRunner tachometer on his site: Analog Planet
Michael Fremer just posted his review of the Falcon PSU and RoadRunner tachometer on his site: Analog Planet
Looking at doing a higher power version of the PSU; just received the proto PCBs from the fab house will hopefully be able to build a couple of them this week.
What would be a reasonable upper power limit for the new design? VPI seems to max out at ~10W but some of the Garrard and Lencos have higher power requirements. Aside from broadcast transcription tables, what is the (reasonable) max power the new version should produce?
What would be a reasonable upper power limit for the new design? VPI seems to max out at ~10W but some of the Garrard and Lencos have higher power requirements. Aside from broadcast transcription tables, what is the (reasonable) max power the new version should produce?
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