Some unusual units

Been reading a book on the 2nd Guards Tank army and I came across two units with some unusual equipment. They were the 9th Separate Signal Battalion and the 33rd Coastal Artillery Battalion or Battery( Both are used in the text)interestingly they are both armed with tanks, T-34s with the signal battalion and T-70s with the artillery. There are not many only 3-5 for the signals and 6 for the artillery.
So what are they there for? In fact I have not found out yet, my google-fu has been a failure. But I do have an hypothesis.
The easy one is the signal battalion. Tanks have radios, even some Soviet ones. Which means they have the ability to communicate with each other. There is unfortunately one problem in making this an easy task. This lies with the radios and the provision of those radios to the troops and their commanders. It is that there are often many different types of radios all operating off different frequencies. You might be aware of the difficulties had by airforces had in communicating with ground forces and even infantry with artillery. Then there are also some examples of armoured cars a reconnaissance vehicle being used on liaison duties all because they have radios. now using tanks on this sort of duty is a stretch I grant, but the Soviets are often short of communication equipment rather than tanks. So the radios may be more valuable than the the guns. Thereby making the decision to allocate some tanks to the signal battalion a sensible one.
The same logic also applies to the artillery tanks. Giving the artillery which has its own communication network its own tanks makes sense. It was not an uncommon occurrence in other armies to provide forward observers with vehicles including tanks so they could keep with the advancing troops. What is strange is the gathering of so many in what is called a coastal artillery unit. The soviets were often short of specialists due to their horrendous losses so a central pool of them makes some sense. It is also possible that these specialists came from a coastal artillery unit hence the name. Yet most artillery in a tank army is either direct fire or short range so there is limited for specialist artillery crew. It is still a mystery.
Well thats it hopefully I will find evidence to test these hypothesis. But they may make an interesting attachment to any army.