Every time Christmas be imminent, I wish that the Santa Claus or someone else would put a huge sack full of voltage-proof capacitors with the most different values in front of the door (but no old and defective). Such devices like the Grundig TK 7 here probably show how it comes to such a wish. But more on this. This tape recorder here is something like the bigger brother of the TK 5. It looks at first glance almost like this, but differs in a few subtleties from the good old TK 5. The TK 7 allows to switch between two tape speeds. The additional tape speed of 19 centimeters per second makes the tape consumption significantly higher, but the higher tape speed leads to a much better sound, the next topic: the three built-in speakers. In contrast to the TK 5, the TK 7 has three loudspeakers. One of these is located on the front of the unit, two are installed on the side. The three loudspeakers in combination with the higher band speed ensure a rich sound of the unit.

Apart from the few differences, the Grundig TK 7 looks almost like a TK 5 with two tape speeds, which ultimately also it is. This particularly gets clear when looking at only the top cover of the unit, as shown in this picture. The control elements are the same as those of the TK 5, if the switch for the two belt speeds is omitted. The operation of the device with alternating rewinding and recording or playback is solved too complicated. First, the right function switch must be switched to the rewinding or the recording and playback. The rewinding itself is controlled by the lever in the cover for the audio head. If one searches for a certain tape point which has not been marked by the tape counter or a corresponding counter reading, then the operation of the device is found to be somewhat cumbersome when searching for that band point.

The interior life of the TK 7 resembles that of the TK 5 very strongly. Everyone who knows the innards of the TK 5, finds his way very quickly. This tape recorder here is still in a slightly better condition than the TK 5 presented on this website. However, the drive belts must also be replaced here. Two of the three drive belts are already torn. Without this, neither the tape counter nor the rewinding of the tape will work.

The switch for the tape speed you can see in the left of the picture. The tape speed is switched purely electrically. The built-in motor runs with two speeds, depending on the position of the speed switch. In many other models, the belt speed is changed mechanically. There, for example, belts are moved over to belt pulleys with other diameters or intermediate gears which then run on drive shafts with different diameters.

In the vicinity of the tape you can see the usual picture, which is often found in older tape recorders from this time. Numerous band particles in the form of brown residues are visible on all components which have come into contact with the tape. Both the tape guides themselves, the sound heads as well as the pressure roller are already covered with a thick layer of belt abrasion. Of course, these parts had to be thoroughly cleaned before commissioning the device for the first time.

The magic eye with the designation EM85 glowed green after the first power-up, as expected. The luminosity is no longer quite the same as a new specimen can be expected. However, it is bright enough that ist is visible well by daylight.

The dismantled chassis of the TK 7 shows the usual picture for this equipment series with the powerful driving motor of the company "Pabst". The electronics are largely seperate from the outside by thick shielding plates to prevent unwanted influences.

This unit has a powerful power amplifier to supply the three built-in loudspeakers. The picture shows the EL84, which fulfills this task. In fact, the unit has a powerful and rich sound, especially at a tape speed of 19 centimeters per second.

The big drive motor of the Grundig tape recorder carries the date of the 6. April of 1956. The device is therefore around 60 years old. Of course, the production date of the motor allows conclusions about the approximate production date of the entire tape recorder. Not only the engine; also the other components of the device seem as if they were built for eternity. The TK 7 is a good example of what rugged devices were once built in germany. Incidentally, it is a so-called external-rotor motor. The outside part is rotatable while the motor winding is fixedly mounted inside the motor. This engine needed new lubricants, since it caused some unpleasant noise during operation.

Lots of brown WIMA capacitors called chocolate sweets as far as the eye can see. In the face of this sight, I don't wanted to set the device in operation to take without first at least some of the capacitors to change. The emphasis is on "actually", since curiosity was ultimately stronger. So I dared to take a step which I would not recommend to anyone: Without replacing any old parts, I started the device. At first, the engine's heavy engine started to move. After the engine started, the magic fan EM85 glowed green. A few seconds later the first tones could be heard from the three loudspeakers, which however had nothing in common with music. It was just a loud cracking and cracking, so I switched off the device quickly.

The WIMA capacitors on the underside of the chassis under the heavy shield are by no means the only capacitors that should be replaced in these devices. Also the ones between drive and electronics should be changed. The picture above shows one of these specimens, which is well hidden. Another capacitor can be found in the back of the tape recorder. However, the replacement of these capacitors is anything but easy. Nevertheless, I took the trouble and exchanged the defective capacitors.

This picture shows the three loudspeakers in the case, which have a very good sound. The main loudspeaker at the front of the tape recorder is somewhat larger than the loudspeaker, which was installed in the TK 5. The two smaller loudspeakers are connected via a bipolar capacitors (the two small loudspeakers are connected in series).

The tape recorder shown during the rewinding, in which the motor has a much higher current consumption than during normal operation. The control lamp on the right above the function switch is intended to remind the user not to use the rewinding operation longer than necessary. In the operating instructions for the TK 5, which also uses this technique, it is said: "This position should therefore never be used as a rest position, but only during the actual rewinding process. A red warning lamp shows you very clearly the operating state " Fast speed." (Quote end)

After the exchange of the WIMA chocolate bonbons, the amplifier part of the device will again function flawlessly. Especially the recordings, which were made with 19 centimeters per second, sounds surprisingly good. Thanks to the three built-in speakers and the wooden case, the unit has a full sound. All sounds are reproduced cleanly. Considering the time the device was manufactured, the sound quality is astonishingly good. According to the technical data, this unit covers the entire audible range. This is perhaps one of the first devices that could record the entire audible frequency range, at least among the home tape recorders.