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Top Gear - Sound Rotator

PostPosted: 05 Jun 2008, 20:08
by borislavgajic
not very clear pictures,but...... :wink:

Re: TOP GEAR sound rotator ...guts

PostPosted: 06 Jun 2008, 02:27
by MoreCowbell
I dig the old stripboard layout. I wish the pics were more clear, but I'm sure it was a PITA to get pictures of a rare old unit like that in the first place....

Thanks... :D

Re: TOP GEAR sound rotator ...guts

PostPosted: 06 Jun 2008, 09:50
by Bernardduur
Wow..... that looks really nice...... what does it do? I "guess" chorus and tremolo????

Some better pics here although they won't add much :)

Re: TOP GEAR sound rotator ...guts

PostPosted: 06 Jun 2008, 10:26
by borislavgajic
it has 4 ldr's ...placed around light bulb........so it is IMHO transistor vibrato..or phaser... :D
it sounded very dull and muddy ...
I had it for one day only ..long enaugh to take photos....
:horsey:
http://www.harpamps.com/schematics/univibe.pdf

Re: TOP GEAR sound rotator ...guts

PostPosted: 06 Jun 2008, 10:38
by DiscoFreq

Re: TOP GEAR sound rotator ...guts

PostPosted: 28 Mar 2009, 16:38
by borislavgajic
I could get to this pedal again........so is somebody interested to trace this .....and to help me fixing it......sound was not sharp (clear)........bad capacitors??? something else......

if there is any interest,I will get to it :thumbsup

boris

Re: Top Gear - Sound Rotator

PostPosted: 30 May 2018, 12:10
by Professor SourTone
borislavgajic wrote:I could get to this pedal again........so is somebody interested to trace this .....and to help me fixing it......sound was not sharp (clear)........bad capacitors??? something else......

if there is any interest,I will get to it :thumbsup

boris


Boris - its possible I now own this pedal, as it came to me from Serbia - is there a schematic anywhere?

Re: Top Gear - Sound Rotator

PostPosted: 21 Jun 2018, 18:28
by Professor SourTone
It is now being looked at - lots of things wrong with it, bad photocell, oscillator, transformer buzz. Wet still very dull and wet/dry not "summing", whatever that means. It will sound very different when fixed, I suspect. H

Re: Top Gear - Sound Rotator

PostPosted: 24 Jun 2018, 23:12
by Professor SourTone

Re: Top Gear - Sound Rotator *now with circuit*

PostPosted: 25 Jun 2018, 17:08
by Professor SourTone
Herewith circuit diagram + post-fix gutshots by Dan Coggins of Dinosaural, although he stresses that without rebuilding it, the oscillator section may not be 100% correct.

It had a dead RPY58A photoresistor (replaced with ORP12, similar functionally), oscillator needed tuning, lube trimpots, fix buzzing transformer, dry joint on level pot.

One mod, 22k "straight blend" mod resistor across bypass switch to brighten it up. Buffer recommended as input impedance very low.

https://flic.kr/s/aHsmi83jTG

Its not arrived home yet, but the IG link in my previous post suggest its a changed beast!

Re: Top Gear - Sound Rotator

PostPosted: 26 Jun 2018, 08:43
by Zokk
Hi, please could you post the pictures on another media: both links don't work for me.
Thanks.

Re: Top Gear - Sound Rotator

PostPosted: 26 Jun 2018, 10:19
by Scruffie
And here I was thinking it was just going to turn out to be another UniVibe, that actually looks interesting, seems it's just a transistor based version of the later 'Rotator'. I'll be interested to hear how it sounds, I can't quite picture it.

Re: Top Gear - Sound Rotator

PostPosted: 26 Jun 2018, 15:16
by Nocentelli
Scruffie wrote:interested to hear how it sounds, I can't quite picture it.


I'm also intrigued. If you can't see the flickr schematic, it's like four colorsound inductor-less twin-T wah circuits in parallel but all tuned to different bands, and all modulated by a (PSO?) LFO. I am going to type thing out with a LED instead of the lamp.

Re: Top Gear - Sound Rotator

PostPosted: 26 Jun 2018, 22:38
by Professor SourTone
Zokk wrote:Hi, please could you post the pictures on another media: both links don't work for me.
Thanks.


I will have a go - what’s the recommended way nowadays, photobucket is hopeless now.

Re: Top Gear - Sound Rotator

PostPosted: 26 Jun 2018, 22:41
by Professor SourTone
Nocentelli wrote:
Scruffie wrote:interested to hear how it sounds, I can't quite picture it.


I'm also intrigued. If you can't see the flickr schematic, it's like four colorsound inductor-less twin-T wah circuits in parallel but all tuned to different bands, and all modulated by a (PSO?) LFO. I am going to type thing out with a LED instead of the lamp.


This from Dan - “A view of the audio filter board. There are four summed (parallel) band-pass filters using Wien-bridge networks, whose frequency bands are roughly an octave apart and each are adjusted to be on the threshold of resonance using individual trimpots. The four of these single transistor stages added together provides four deep notches that sweep up and down together and carve out the input signal. The additional resistor provides more straight signal bandwidth for these to cancel agains @Level=8.”

Re: Top Gear - Sound Rotator

PostPosted: 27 Jun 2018, 08:33
by Zokk
Professor SourTone wrote:I will have a go - what’s the recommended way nowadays, photobucket is hopeless now.


Thanks, you can upload the pictures directly on the forum, check the tab below when you write a message :"upload attachment".

Re: Top Gear - Sound Rotator

PostPosted: 24 Aug 2018, 20:05
by Professor SourTone
Sorry delay

Re: Top Gear - Sound Rotator

PostPosted: 25 Aug 2018, 00:46
by EddieTavares
How does it sound?