Grundig TK14

[rockinmark]

Hi.

My first reel to reel is a Grundig TK14. It seems to work OK, fast forward, rewind and play work OK.
I haven't got a mic; when I tried to record by pushing the white and the start button this did not start recording over the tape.
Not sure if I'm doing something wrong or it is not working.

Any help please.

Mark

[saxmaniac]

Keeping the white button pressed while pressing the start key should enable recording. The white button should stay down on its own while the record mode is running. If the machine has not been used for a long time then a number of components may need checking/changing before it is powered up, or damage to valves/transformers may happen. If the machine is working fine but just not recording, the action of the record/replay switch would be the first thing to check as it may be very dirty.

[rockinmark]

The button stays down but I have no mic or leads with DIN plug but I was thinking it should still wipe the tape. This was not happening, also not sure what DIN plug to use and how to wire it. The unit can take a 5 pin plug but I thought it is 3 pin.

Mark

[Refugee]

I have got one too.
Mine has the German version of mustard capacitors in it and the control grid voltage on the output valve was fine. It did play tape if it was pulled through the heads by hand.
The capstan belt dropped right out of the slots in the base of the cabinet.
It obviously needs new belts.

[AndiiT]

Originally Posted by rockinmark

….. the unit can take a 5 pin plug but I thought it is 3 pin….

Hi,
The 5 pin sockets on the TK14 are only wired for 3 pin, the spare pins are to allow a 5 pin plug to be fitted in the socket. DIN sockets are numbered anticlockwise with the locating keyway at the bottom (i.e. pointing to the floor) based on the original 3 pin system, so the farthest left pin is pin 1 the pin directly above the keyway is pin 2 and the farthest right hand pin is pin 3, on a 5 pin socket pin 4 sits between pins 1 and 2 and pin 5 sits between pin 2 and 3.

There is quite a bit of information here

On tape recorders pin 1, (and 4) are usually inputs and pin 3 (and 5) are usually outputs, this is certainly the case with the centre socket on your TK14's input panel.

Regarding you erase fault, try cleaning the erase head before looking for other causes of the fault, although due to the age of the machine I would suspect that the cause of your fault may require further investigation of the circuit.


Regards

Andrew

[rockinmark]

I will try and make a DIN plug to test.

Thanks for the help.

[Nuvistor]

If it has the toffee Wima capacitors in it they will need to be replaced. When these came in to the workshop for repair, unless it was a mechanical fault, changing the caps cured most if not all the faults.
The were a nice tape recorder, much better than the run of the mill UK ones at that time. Probably a lot more money though.
Frank
Edit. if it is not wiping the tape and the switch is OK the bias osc is probably not working, Wima caps?

[rockinmark]

Just one thing, if a tape has been recorded on a 4 track can you re-record on a two track tape?

[Nuvistor]

It depends on the track layout, if the two track of the 4 track are laid out next to each other than yes, although it is possible it may not erase all the old recording it should do most. If the tracks are alternate on the 4 track tape you would need to pass the tape past the heads on both sides of the tape.
I presume you have checked both heads are clean, it does not take a lot of build up of shed oxide to stop or reduce the working of the tape heads.
Frank

[rockinmark]

Thank you, Frank.

I will have a look at the heads again, I did a bit of a clean up.

Before I take it apart I was trying to get a copy of the service manual in English; I'm not sure how you get to the electronics.

[AC/HL]

Service data here: http://www.service-data.com/section.php/3451/1/tk14

[rockinmark]

Thank you bill
The unit is recording but quite and the only tape I have is second hand and 4 track

[Nuvistor]

It will record on that tape, the only problem is it may not completely ease the 4 track until you have recorded on both sides, depends on how the 4 track was laid out, , if the erase is working correctly after recording on both sides the tape will be ok.

"quite" ? typo for quiet? if quiet and the heads are clean, you could check for head wear, the tape wearing a the tape heads down, easy to see, they could also be magnetised. After that you are going to need to check out the electronics.

[rockinmark]

It plays the tapes and holy is OK when I record on both sides I still have the original recording as well and this is louder than my recording how do you no if they are magnetised if it has not been used for a long time wouldn't it be run down by now does this affect the recordings

[ben]

If the erase head is clean and oscillator working, you should hear next to nothing of the original recording on the tape after recording on your machine. No matter what track system it was made on.

In order to progress with this, please do the following:
-clean the heads (as Andrew suggested in post 5)
-check wires to heads
-open the unit and check for loose wires, burned components etc.
-clean the rec-pb slide switch (internal) - use servisol spray or similar.

Post back with an update when you have checked these.

It may also be worth getting another tape, preferably a known brand. Plenty on ebay but be sure to get a 5 inch spool - I think these units can't take 7 inch reels..

[DOFFERY]

I don't know how technical you are but without measurements it is rather difficult, however three known facts about the TK 14(not the 14L)

ECL 86 prone to problems, also the 3300pf cap. across the primary of the osc. coil , known to fail also

adjustment of C 37. If you can measure, you should have about 40 volts across the R/P head & 60 across the erase head.

Colin.

[Refugee]

It sounds like the bias/erase oscillator is not running.
Check the continuity of the erase head with the wires disconnected and also the secondary of the bias oscillator transformer.

[rockinmark]

Thanks for the advice I will check a do the thing that Ben has said first I will check continuity of the head I'm not sure what thebias/erase oscillator is or where the osc coil is
I'm not sure where to put my meter to check voltages of the heads colin

[DOFFERY]

Check directly across the head terminals.

Colin.

[Refugee]

You need to disconnect the wires to the erase head and check the head and also the disconnected wire as it will be connected to the coil.