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Vintage Tape (Audio), Cassette, Wire and Magnetic Disc Recorders and Players Open-reel tape recorders, cassette recorders, 8-track players etc.

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Old 6th Jan 2023, 3:57 pm   #21
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Default Re: Uher Royal Stereo 784

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It is possible to control the speed (downwards) on a motor that has a run capacitor by connecting a rheostat across the capacitor terminals and connecting the supply wire to the wiper of the rheostat but once the wiper reaches just beyond the mid point of the rheostat the motor will start to run backwards. I did this on some older Grundig recorders in my (much) younger days.

That's helpful thank you! In theory, could I not hook up the rheostat directly between the power source and the motor (in case there isn't a run cap)?
No, the motors are mains frequency synchronous and hence will always try to run at the normally correct speed but produce less torque.
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Old 6th Jan 2023, 7:04 pm   #22
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Default Re: Uher Royal Stereo 784

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Taken from the Uher Royal Stereo Operating Instructions Manual here is info covering Playback through external speakers, Echo, Sound on Sound, Multi-Play and Dia-Pilot.

The Playback through external speakers on pages 17 & 19 is the same as the German text on page 10 in Post 1 link.

The manual does not appear to specify which Royal model it covers but I am fairly sure it is for the 784.

David
Oh, thank you David! I translated part of this from German. Quite useful indeed!
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Old 6th Jan 2023, 7:04 pm   #23
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Default Re: Uher Royal Stereo 784

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If you want something that you can use for variable speed tape echo then you'd be better off with something like a Philips N4504, N4506, N4512 or N4515. There are probably others in the Philips range that would work but I know for sure that these would work because they're all based on a similar transport and I've used my N4515 as a variable speed echo unit by connecting a variable resistor in parallel with the preset that controls the 1 7/8ips speed. This gave me a speed range from just over 1 7/8ips up to something like 15ips.
I got very interested by the UHER, since I've already the 4000 report monitor and they share the same speed settings. I am currently mostly using that one for tape echo since I have removed the bult in speed trim pot and replaced it with an external pot knob on the front panel . So in other words I have fine adjustment over the speed for each speed setting. That pretty much gives me almost any echo time I might need. I have modifications on all of the units I own at the moment but every one of them does not compete with echo time ranges compared to the UHER. The downside is, it's mono..

I recently discovered how to set up a stereo 3 head deck to make ping pong echo. I can even link this mode to an external switch very easily to turn it on and off. My portable stereo decks are the Marantz CP430 and the Marantz Superscope CD330. The CP430 has a small pitch range and the heads are quite close. I have a modification on that unit which drops the motor speed with a switch (as much as I could have as any lower than what I have it now just shuts off the motor). It's very similar to the PMD222 which has a standard and low speed switch built in. The CD330 I did in a different way. I took out the motor speed control PCB from the motor and I added a switch which swaps between a PWM controller and the stock speed PCB. That way I can switch to stock speed for normal playback and recording functions. Yet again, the CD330 does not go as slow as the UHER. So.. the Royal really triggered my interest and not only because of the stereo functionallity but also because of the echo built in setting and it seems much more affordable compared to say a UHER 4400 or 4200 RM.

I think I talked myself into getting the one I found, I am just waiting for a confirmation it actually records. They should let me know Monday. I am still trying to understand what chances I have to gain variable speed control over the motor.
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Old 6th Jan 2023, 7:11 pm   #24
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Default Re: Uher Royal Stereo 784

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It is possible to control the speed (downwards) on a motor that has a run capacitor by connecting a rheostat across the capacitor terminals and connecting the supply wire to the wiper of the rheostat but once the wiper reaches just beyond the mid point of the rheostat the motor will start to run backwards. I did this on some older Grundig recorders in my (much) younger days.

That's helpful thank you! In theory, could I not hook up the rheostat directly between the power source and the motor (in case there isn't a run cap)?
No, the motors are mains frequency synchronous and hence will always try to run at the normally correct speed but produce less torque.
Thank you for the response! I wasn't too hopefull it would work that way. Either way, from the small research I've done, in case there is no run capacitor, I think using a Variable Frequency Drive should do make this work, or am I wrong?
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Old 6th Jan 2023, 9:17 pm   #25
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Default Re: Uher Royal Stereo 784

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That's helpful thank you! In theory, could I not hook up the rheostat directly between the power source and the motor (in case there isn't a run cap)?
No, the motors are mains frequency synchronous and hence will always try to run at the normally correct speed but produce less torque.
Thank you for the response! I wasn't too hopefull it would work that way. Either way, from the small research I've done, in case there is no run capacitor, I think using a Variable Frequency Drive should do make this work, or am I wrong?
That would work
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Old 17th Jan 2023, 8:00 pm   #26
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Default Re: Uher Royal Stereo 784

I have received a video demo from the person selling one of these. I know for a fact this tape machine has three heads. One things is unclear to me. In the video they are engang the record function and I notice that after they press stop while the red button is engaged you can hear the input source until they disengage the red button. I tried looking up through the manual and on the device itself (from photos), but I can't seem to find a switch between tape and source. Given it has three heads, am I right to assume the third head is related to the built in echo mode? Here is the video in question

https://www.youtube.com/watch?v=7aAXiafmkgw
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Old 17th Jan 2023, 10:36 pm   #27
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Default Re: Uher Royal Stereo 784

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Just realised that I must have the Royal Stereo 784 or the 2 track version the 782.

Have never powered it up or even really looked at it, I must locate it and check it out.

David
Not sure now if I actually have a Uher Royal Stereo 784 because I have just found a Uher 724 which is a similar recorder.

David
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Old 19th Jan 2023, 12:51 am   #28
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Default Re: Uher Royal Stereo 784

The English Operating Instructions manual explains that during recording if you rotate the balance control anticlockwise the monitored signal you hear will be the source and if the balance control is rotated fully clockwise, the signal heard will be the off tape monitoring.

Tomorrow will scan the page and attach.

David
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Old 19th Jan 2023, 6:21 pm   #29
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Default Re: Uher Royal Stereo 784

I now see that the information in Post 28 appears to be only referenced in the Mono Recording section ?

David
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Old 19th Jan 2023, 6:45 pm   #30
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Default Re: Uher Royal Stereo 784

Hi David. Thank you for taking the time to send this information through! I looked over it. This is helpful. I am still trying to make sense of how stereo operates. For example when echo is enabled how exactly does it work? Usually in order to create an echo chain there is a need of external mixer to feed back the signal to the recorder. Is the echo for the royal actually stereo? And then again is it as simple as feeding the input with a signal to get echo from the output? I really need to dig in deeper and find the entire manual in English. I would definitely be looking at having full stereo monitoring while recording.
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Old 20th Jan 2023, 10:46 am   #31
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Default Re: Uher Royal Stereo 784

Other than whats in Posts 3 and 19 I know nothing about Echo recording/playback.

The Echo info from the manual at Post 19 maybe indicates that the echo can be mono or stereo because it says for example "set the Echo to 1-4 position for recording on tracks 1 and/or 4.

Do not think there is anything else in the Instructions manual about Echo.

Have had no time to look at the schematic.

David
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Old 2nd Feb 2023, 10:22 pm   #32
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Default Re: Uher Royal Stereo 784

Hi David. I went ahead and purchased the Royal De Luxe 784E. It arrived a few days ago and it works fairly well for such an old machine. Only thing that made an impression so far is a noise that comes and goes when the unit is positioned vertically. I belive it's from the motor. Reajusting the unit position could sometimes result in disabling that noise. I do not yet have output cables to know if it is transmitted to the output signal. I was wondering if it's possible to ask you for the entire (or the rest of) the user manual?

Kyle
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Old 2nd Feb 2023, 11:42 pm   #33
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Default Re: Uher Royal Stereo 784

Kyle, I will try and do it tomorrow.

David
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Old 2nd Feb 2023, 11:54 pm   #34
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Default Re: Uher Royal Stereo 784

Some machines that are designed to operate horizontally can be noisy/very noisy when operated vertically, this can be because the flywheel/capstan shaft can easily move in the lateral direction when unit vertical (especially for machines where the top of the capstan shaft is not retained in an upper bearing), when operated horizontally the weight of the flywheel keeps the flywheel/capstan shaft in the lowered position (resting in lower bearing/on lower bearing pad) fairly stable position wise.

David
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Old 3rd Feb 2023, 9:00 am   #35
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Default Re: Uher Royal Stereo 784

Looking at the video in post 26 I don't think this machine is designed to operate vertically as there appears to be no way to retain the spools.
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Old 3rd Feb 2023, 10:33 am   #36
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Default Re: Uher Royal Stereo 784

Is this Royal Stereo machine actually identified anywhere as model 784 ? i.e. maybe on the ident plate in the cable stowage area at the rear.

David
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Old 3rd Feb 2023, 11:09 am   #37
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Default Re: Uher Royal Stereo 784

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Just realised that I must have the Royal Stereo 784 or the 2 track version the 782.

Have never powered it up or even really looked at it, I must locate it and check it out.

David
Not sure now if I actually have a Uher Royal Stereo 784 because I have just found a Uher 724 which is a similar recorder.

David
Now have just found my 784 (model # on ident plate in cable stowage area).

Not 100% identical to the one shown in Post 26, on mine the 4 indicator light windows around the VU meters are small.

David
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Old 3rd Feb 2023, 11:26 am   #38
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Default Re: Uher Royal Stereo 784

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Looking at the video in post 26 I don't think this machine is designed to operate vertically as there appears to be no way to retain the spools.
Yes no spool retaining mechanism.

On my 784 the spool tridents were sheared off when it arrived quite some time back.

The seller had shipped it with full tape spool and empty spool fitted but with no packing in the lid around the spools with result that during shipping and the heavy abuse they receive, the spool tridents had completely sheared off.

Hope to repair them one day when I can find time.

David
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Old 3rd Feb 2023, 5:53 pm   #39
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Default Re: Uher Royal Stereo 784

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Kyle, I will try and do it tomorrow.

David
Thank you David! There is no rush so whenever suits you best works for me!
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Old 3rd Feb 2023, 6:17 pm   #40
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Default Re: Uher Royal Stereo 784

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Originally Posted by DMcMahon View Post
Some machines that are designed to operate horizontally can be noisy/very noisy when operated vertically, this can be because the flywheel/capstan shaft can easily move in the lateral direction when unit vertical (especially for machines where the top of the capstan shaft is not retained in an upper bearing), when operated horizontally the weight of the flywheel keeps the flywheel/capstan shaft in the lowered position (resting in lower bearing/on lower bearing pad) fairly stable position wise.

David
I can confirm the machine seems to be indeed designed to be placed horizontally. There is no locking mechanism on mine. I taken off the front and back pannels of the machine. The capstan is attached to the motor shaft. That entire piece does have some loose movement if I am to hold it and pull/push. When the motor turns on, if I am to press the capstan with my finger, the noise disappears. The unit is model 784E. I have attached photos.
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Last edited by sourbiscuits; 3rd Feb 2023 at 6:37 pm.
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