Нужно сообщить диспетчеру.

Нужно means necessary / needed / must be done.

In Russian, this kind of sentence is often impersonal, so there is no subject like it.
English says It is necessary to inform the dispatcher, but Russian simply says:

Нужно сообщить диспетчеру.

Literally, it is closer to Necessary to inform the dispatcher.

So нужно is doing the job of expressing necessity, without needing a subject.

After нужно, Russian commonly uses the infinitive to say what action is necessary.

So the pattern is:

нужно + infinitive

Examples:

• Нужно подождать. — It is necessary to wait.
• Нужно позвонить. — It is necessary to call.
• Нужно сообщить диспетчеру. — It is necessary to inform the dispatcher.

This is a very common structure in Russian.

This is a question of aspect.

• сообщить = perfective
• сообщать = imperfective

In this sentence, сообщить is used because it refers to a single completed action: the dispatcher needs to be informed.

So Нужно сообщить диспетчеру suggests:

• the information has to be passed on
• the action should be completed

If you used сообщать, it would sound more like:

• informing in general
• repeated informing
• an ongoing process

For a one-time necessary action, сообщить is the normal choice.

Because it is in the dative case.

The verb сообщить often takes:

• the person receiving the information in the dative
• the thing being communicated in the accusative or as a clause

So:

• сообщить диспетчеру — inform the dispatcher
• сообщить диспетчеру новость — inform the dispatcher of the news
• сообщить диспетчеру, что... — inform the dispatcher that...

The ending -у shows the dative singular of диспетчер.

Yes, the sentence does not state what needs to be communicated. Russian often leaves this unstated when it is obvious from context.

So Нужно сообщить диспетчеру means:

• It is necessary to inform the dispatcher
• The dispatcher needs to be notified

But it does not say about what. That would have to come from the situation, or be added:

• Нужно сообщить диспетчеру об аварии. — It is necessary to inform the dispatcher about the accident.
• Нужно сообщить диспетчеру, что поезд задерживается. — It is necessary to inform the dispatcher that the train is delayed.

Yes. In many situations, нужно and надо are very close in meaning.

• Нужно сообщить диспетчеру.
• Надо сообщить диспетчеру.

Both can mean It’s necessary to inform the dispatcher or We need to inform the dispatcher.

A rough difference:

• надо often sounds a bit more conversational
• нужно can sound slightly more neutral or formal

But in everyday speech, they are often interchangeable.

Yes, it is not stated directly.

Russian often leaves the doer of the action unstated if it is obvious or unimportant. So this sentence can mean:

• Someone needs to inform the dispatcher
• We need to inform the dispatcher
• You need to inform the dispatcher

If you want to specify who, you can add a dative pronoun:

• Мне нужно сообщить диспетчеру. — I need to inform the dispatcher.
• Нам нужно сообщить диспетчеру. — We need to inform the dispatcher.
• Вам нужно сообщить диспетчеру. — You need to inform the dispatcher.

Yes. Russian word order is flexible.

The neutral order here is:

Нужно сообщить диспетчеру.

But you can also say:

• Диспетчеру нужно сообщить.
• Сообщить диспетчеру нужно.

These versions are grammatically possible, but the emphasis changes slightly.

• Нужно сообщить диспетчеру = neutral
• Диспетчеру нужно сообщить = puts more focus on the dispatcher
• Сообщить диспетчеру нужно = can sound more emphatic or contrastive, depending on context

For most learners, the original order is the safest default.

Диспетчер usually means a person who coordinates or controls operations, depending on context.

Possible English translations include:

• dispatcher
• controller
• operator

For example, it could refer to:

• a transport dispatcher
• a railway dispatcher
• an emergency dispatch operator
• a logistics coordinator

So the exact English word depends on the situation, even though dispatcher is the most direct translation.

The stress is:

• нУжно
• сообщИть
• диспЕтчеру

So the sentence is pronounced roughly like:

НУЖ-на са-аб-ЩИТЬ ди-СПЕ-ти-ру

A more careful breakdown:

• нужно → НУЖ-но
• сообщить → stress on -щить
• диспетчеру → stress on спе

Pay special attention to сообщить, because the consonant cluster can be tricky for English speakers.