At your risk.
This is the 4th Uher report bought. It belongs to Vicky.
It had been bought a few months ago at eBay.de.
Description said belt replaced. This is an alarm statement.
Why?
Apparently when belt was replaced it had been forgotten to include the metal barrel which acts as a spacer for the circuit board. While fastening the screw the circuit board had been severely bent and some tracks broken.
When it arrived it had been packaged with all the weight of the machine sitting on the handle.
Something was rattling inside which was the aluminum barrel.
It even affected operation. Fortunately it was removed after a small test before further damage done.
The unit would oscillate by mechanical feedback making the playback active then inactive then active or vice versa in a quick dangerous for the ears squeeling loop.
One day while in Vicky's garden a very faint cold joint had been discovered. After resoldering playback started to be operative. It still was internment due to the torn tracks.
After all visible torn tracks were bridged and soldered with wirewrap wire, the unit was still interminent.
Last Thursday (after replacing batteries with Fujitsu) a digital voltmeter had been connected between solders of the same track and a voltage (3V) was observed together with a clicking sound.
This immediately indicated another torn but not visibly damaged track. After bridging the Uher started to normally operate without interminent temperament.
Playback was dull on the left channel and low volume on the right. The difference in volume was due to the recording made by the 3rd Uher which does not operate properly.
Some signal tracing had been done for the cause of lack of treble on upper track. Accidentally all the spool was unwound which meant that the Uher had to be closed again in order to safely replace the tape on the reel. And it was time to have lunch.
The idea then came to reclean the heads.
And yes it turned out to be a head dirt problem.
Heads were cleaned for about half an hour very casually with isopropyl alcohol using a wooden toothpick covered by soft tissue paper for every few seconds of head cleaning.
Now both tracks record and playback normally with very nice sound.
By recording a test CD with tones it was found that although the Sony CD Walkman sends equal voltage for each tone, the Uher VU meter needles move from mid position to full modulation at very low test tone frequency and very high one.
Play back is even in frequency responce with the exception of the right channel being many more dBs below the other channel at 20KHz.
This is something to be looked at and a calibration tape should be ordered.
Then Walk o nBuy - Dionna Warwick had been recorded and it played marvelously. Much better sounding that the playback of the source CD on Sony Walkman.
This particular Uher makes a lot of mechanical noise.
Before the last track repair the belt had been removed and it was found to be extremely short placing a heavy load on the motor. It had been replaced with a larger diameter belt. Noise was quieter but still high.
When listening to the test tones playback a subtle vibrato effect can be heard at say the high frequency test tone recordings. It is a nice vibrato that reminds a singer. So it may prove that this may add to the listenability and smoothness of sound.
signal path:
CD source - Sony CD Walkman - Uher 4200 report - BASF SM 911 - Uher 4200 on playback - Realistic disco mixer 32-1101A - Sennheiser HD 580 headphones
It has been observed that the B 109B transistors used at the input (EMI TG12345 mixer uses the same BC109 transistors). These transistors had the S logo indication that they are made by Siemens.
While searching on Google Uher 5in reel it was seen that NASA used the Uher Report 4400 on their experiments.
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