The MTB 82 trolleybus

T151 (72)
The T151 MTB 82 trolleybus in Városliget (City Park)

The story of the MTB trolleybuses in Budapest

In 1949 the tram line 10 was replaced by trolleybus, with also lengthening the line through the Városliget (City Park) to Erzsébet királyné útja. In May 1949, the cable was set in the outer section, and the preparation of the drivers started with the three Óbuda car.
Trolleybus T100 in its original state, before entering into service. The trolleybuses had originally this more elegant liveries, which was corrected to the one seen below.
The T106 trolleybus before the start of the service at Erzsébet királyné útja (street).  The waving arms signalling the turns are missing.
On 26th October 1949 arrived the first shipment of the MTB 82 trolleybuses, on 1st December the 25th was in Budapest. One more vehicle above these was bought: the exhibitor car of the BNV (Budapest International Fair) of 1949. 
The official exam of the first trolleybuses was on 24th November 1949. The numbers of the the first trolleybuses became T100-T125. The public opening was on 21st December, on the 70th birthday of Stalin. Possibly the meaning of the new line number 70 should not be further explained... Though originally the line was planned to be opened on the 32st anniversary of the Sowiet Revolution on 7th November, but the construction works were delayed. 

Until 1953 further MTBs were bought: 
new vehicles (pieces)
Alltogether 53 MTB 82 trolleybuses were supplied to Budapest, after the Sowiet Union did not have the capacity to sell more.

T100 (70)
The first...
The T100 on the opening ceremony of line 70.
In the Sowiet Union the production of trolleybuses started in 1936 in the city ofJaroslavl (that is situated near the river Volga). During the war the Auto-Motor Institute made uniform plans of autobuses and trolleybuses; the look of the cars werevery similar to the products of the US company General Motors. After the war the first of the type JaTB-4 was made in Jaroslavl. Soon the production was movedto the Moscow (Tushino) Airplane Factory (Moscowsky Aviatsiony Zavod '82); the nameMTB 82 was the abbreviation of Trolleybus of Moscow. The first 28 pieces to Budapest were made here. 

On 28th February 1950 the Minister Council of the Sowiet Union assigned the "Uritsky" factory in the city of Engels for production of trolleybuses (the city ofEngels is also along the river Volga opposite to Saratov). The first trolleybus was ready on 1st May 1951. This was the origin of the 1952 series of MTB's to Budapest, which could have also bear the name ZIU (Zavod Imeny Uritskowo).

The T111 trolleybus in the '50s at Damjanich depot- again in festival outlook
In the '50s the official propaganda made a cult around these trolleybuses. Forexample the newspapers at the time wrote about an accident, where "a notorious driverdestroyed the wonderful present of comrade Stalin and the Sowiet Union".

Then in the revolution of 1956 two MTB trolleybus (T139, T140) was damaged so badly during the fights, that in 1957 they were scrapped. 

On the 19th June 1958 at the line 71 the sitting conductor service was introduced experimentally. For this reason five MTBs' body were modified: they obtained wider doors and the frontal look was redesigned too. Later the sitting conductor service was also used on cars without rebuilding, until the tariffication reform in 1966.

T145 (70)
At the end of Kálmán Imre utca (street) the T145 and another MTB trolleybus. 
In the '50s at the rear tram shields were used on the bumper. In the '60s the shield were put behind the rear windscreen.
The remaining 51 cars were scrapped between 1964-67, instead of them new ZIU-5 trolleybuses were bought. The last of them (scrapped in 1967) were in service on 31st December 1966 on line 79: these were T103, T130, T131, T135, T137, T151
scrapped MTBs (pieces)

Not all of the trolleybuses were taken apart, some of them became trailer of lorries. This way escaped one MTB 82, which is today at Pongrác depot. It is in a bad condition, the renovation is set back since the lack of money.

T143 (70)
The T143 at Május 1. út (street - today Hermina út), in the '60s.
In the '60s the pattern of the coloration was changed.
In the '70s the scrapped MTBs were converted into caravans used by builders. This picture shows trailer UL-055.
Tibor Tildy
Vitézy Dávid
The remaining MTB 82 trolleybus at Pongrác út depot, in 2001. 
This car is one amongst the five, which door was widened. 
The number of the five different trolleybuses are: T100, T128, T132, T134 and T138 (and on photos I found one more: T129).
Dávid Vitézy

Some technical details of the MTB trolleybuses

Data of the trolleybus:

10 365 mm
2 615 mm
height (with lowered trolleys)
3 670 mm
distance of the axles
6 000 mm
8 800 kg
seats / standing places
38 / 37
DK 202/B
116,8 HP (86 kW)
number of cascades: (accelerate / brake)
11 / 3


The MTB trolleybuses had quite large axle distance (6 m), and it was wider than the usual vehicles. This did not cause any handycap in the traffic, but only in turns larger than 13 m of radius were able to go.

The construction was a typical example of the non-self-carrying body: it had a heavy chassis with a built on body. The look of the trolleybus was very similar to the US PCC trolleybuses.

Pálffy workshop
An MTB 82 trolleybus under reparation at Pálffy-workshop. The roboust chassis and the built on body are disengaged. 
From the homepage of Zoltán László
Originally the MTB 82 type had quite narrow doors, which were operated by the driver throug pressure air. The wings of the doors were connected mechanically: they closed or jammed together. The driver had one switch to controll both doors. It had five state: in the middle state the doors were closed, and turning in both direction opened the two doors after each other. Turning back was the way of cosing the doors. There was no signalling for the passengers: the front (exit) door had to be checked by the driver with a look. There was one lamp for checking the state of the rear door.
The driver's place of an MTB with open contactor-box.
Notice the two pedals on both side of the steering wheel, and the door operating switch in the middle of the instrument board.
Cleaning of the interior of the MTB trolleybus, for the opening.

The side windows were the typical PCC standee windows, they could be opened by pulling up.
Inside there were double seats in two row, which made the flowing of the passengers slower. The driver's cabin was quite large, wich was separated from the room by a telescopic door.

On the MTB 82 there was missing the servo for steering, in slow motion the steering was heavy. The driver had to be conscious about this in the traffic (especially at the stops). At larger speeds the steering meant no difficulty.

T120 (70)
The original T120 possibly in 1949, on the opening ceremony. 
The trolleybus has wheel trims, which were later dismanteled.
Five trolleybuses were rebuilt with wider doors for the sitting-conductor service, one of them were T134. 
Not just the doors, but the near windows were modified, and the face of the car became also different. Instead of waving arms index-lights were installed.
The run of these trolleybuses was quiet comparing to the other vehicles at the time. There were some accidents of pedestrians stepping in front the noiseless trolleybuses.

The vehicles had 6 m long steel trolleys, this allowed 4.5 m deviation from the poles. In case of running away too much from the middle, there were lamps signalling the problem. The trolleys were pushing up with the force equivalent of 10 kg. The trolleys had coal inserts to avoid the abrasion of the poles. The current flow through a electric noise filter inside to the electric equippments.

Nagymező utca
In Nagymező utca (street) because of the removal of the tram tracks, a trolleybus had to make an evasion

Electric equippments:

All the Sowiet trolleybuses in Hungary had double coiled motors: these had separate coils for the main circuit and another for the outer exciting circuit. The motor and the resistors were mounted on the chassis. The electric circuit of the MTBs were relatively simple, only contactors were regulating the coupling of the resistors. The contactors were driven according to the accelerator and the brake pedals. These were on both side of the steering wheel, the brake pedal was on the left side. There were rotating cylinders joint to the pedals, and the toes on the cylinders fed the contactors by coupling them on the line voltage. Actually the whole system was using the line voltage, if no voltage was at the poles, the contactors released themself.
The accelerator had 11 cascades, the brake had 3 before the air pressure brake came into action. The relays and contactors situated in boxes in the driver's cabin, they were operating with a substantial noise.
The simplified electric circuit of the MTB 82 trolleybus.
Clicking on the image the circuits of the lighting, the compressor and below the contactor regulation are visible.
The motor is three units on the plan: Motor is the rotating part, Főáramkörű mágnes and Mellékáramkörű mágnes are the main and the outer exciting coils of the motor. On the right side of the motor are the resistors.
LB1, LB2 are the line contactors, R1-R5 are the contactors regulating the resistors in the main circuit, S7-S9 are the contactors in the exciting circuit
B - brake contactor, PMH - overpotential relay, MP - maximal relay, PCC - relay operating the brake signalling lamps in the rear, AB - overpotential (fuse) switch

The acceleration had three stage: in the first cascade all the resistors were inside the circuit with lower outer excitation. With this the trolleybus started relatively smoothly. Then the excitation increased by operating all S contactors, and cascade by cascade all the resistors were short-circuited by the R contactors. In the 8th cascade there was full excitation and no resistors left in the main circuit. With this the trolleybus ran 20 km/h. In the last stage of the acceleration the three S contactors released decreasing the outer excitement: so this last 3 cascades were shunting the motor. With this the vehicle increased its speed up to 50 km/h.
If the accelerator was pressed too rapidly, then the maximal relay released the two line contactors LB1 and LB2. In this case the accelerator pedal had to be released and start again the coupling. If the line voltage disappeared (e.g. tramway crossings) the zero-voltage relay came into action: the bell rang. The line contactors did not work when the voltage returned while the accelerator pedal was pressed: this way the harmful current-impulses were avoided.

It was possible to make a recuperative brake with the MTB. By releasing the accelerator pedal back to the 8th cascade, the trolleybus decreased its speed to 20 km/h with recuperation. If the network was not suitable for recuperation the increasing voltage made PMH overpotential relay to switch to rheostatic brake automatically (with shutting down every main circuit contactors, and operating the B brake contactor). This way the three shunt cascades were the three possible strength of the recuperative brake.
Pressing the brake pedal caused to switch instantly to the rheostatic brake. Then the B contactor short circuited the rotating part of the motor through the resistors, and only the outer excitation circuit remained under voltage. The strength of the brake was regulated by the S contactors. This way the brake was smooth; to make a more efficient brake the driver pressed the pedal to the air pressure brake stage. The feeding of the excitation circuit caused a slight consumption of energy from the pole (the maximal current was around 10 A), but also in case of no voltage, the rheostatc brake did not work.

Two MTB 82 trolleybuses at the cross of Király utca and Izabella utca (street).
In the Izabella utca the trolleybus line was opened in 1952, the picture was possibly taken at this time
homepage of Zoltán László

Though the electric equippment of the MTBs in Hungary was uniform, not all the sowiet MTBs had the same system. There was an MTB 82D type with the starter-regulation of the ZIU-5 and ZIU-9 types. The most interesting was the variant of the MTBs, which had a motor where the rotating part had doubled coils (i.e. the coal-brushes and the commutator were also doubled). With this there was a possibility to make a serial-parallel coupling with a single motor. Also there was a construction with an electric equippment of serial-parallel coupling but with the normal motor. Here in serial cascades the second motor was replaced by a large resistor.
The lights were fed from 550 V of the line voltage. This meant, that on longer dead sections the lights went out, only the emergency lights were lit. There were five bulbs coupled in series, alltogether there was 15 bulbs. A heating was also installed.

T122 (70)
The T122 at Hermina út tram cross, where trolleybus line 70 met tram line 25.
This image was taken in the '50s, the shields near the line number are out of use by this time
From the homepage of Zoltán László
There is one line voltage device is missing: the compressor. It had a 1.5 HP motor, and was regulated by a pressure switch. It turned on under 4 bar, and turned off above 6 bar.

The MTB had a small capacity accumulator, which was charged from a dynamo on the motor-axle. The outside lights, the instrument panel, the horn, the waving arms and the bells were operating from 12 V. A curiosity amongst these are the waving arms, which were signalling the turns. In the late '50s these were replaced with blinking turn signals.

T121 (71)
T121 (71)
The T121 MTB 82 trolleybus at Kossuth tér serving the line 71, in the '50s.
On the first picture near the left mirror the operating waving arm is visible.
An important aspect of the trolleybus traffic is the insulation (since the vehicle is not grounded as trams). The insulation was regularly measured on the MTBs.

Pressure air accessories:

On the MTBs there was three things operating with pressure air: the air brake, the doors and the windscreen wiper. The windscreen wiper was also possible to use by hand.
T125 at Városligeti fasor, in the beginnings of the '60s.
Trolleybus T102 at Podmaniczky utca.

Let's have a look at the MTBs of the Sowiet Union

An MTB trolleybus with a trailer in Leningrad.
The museum trolleybus 1777 of Moscow
Norman Griffiths
An MTB 82 trolleybus on the sowiet Far-East in Usbegistan, at Samarkand

The place of this picture is unknown to me, but it was common in the Sowiet Union, that the ropes of the trolley was just weave on the left side of the car.
The first trolleybus of the capitol city of Belarus, Minsk
Norman Griffiths
Chisinau's (capitol of Moldavia) first trolleybus was also an MTB
Norman Griffiths
In the Sowiet Union from 1947 a tramcar similar to the MTBs was also produced: the type MTV 82. On this picture is tramcar 1079 of Moscow in 1959
W. Tischler
And also a tramway-trailer was made form the type MTV...
The picture was made in Kasan (situated along the river Volga) in 1973: the motorcar 208 is pulling trailer 0208
E. Obst

Every comment is regarded!
Written and translated by: Zoltán Ádám Németh
Thanks for the images to:Zoltán László, Dávid Vitézy and Norman Griffiths. Some interesting links: (MTV-82)