AN/GRC-9 aka "Angry Nine" Military Field Radio

The AN/GRC-9 is a set of components primarily comprised of the RT-77/GRC-9 receiver-transmitter, capable of operating between 2-12 MHz in CW, MCW and AM modes. MCW is a modulated form of CW that can be received by radios that do not have a BFO (i.e. a normal AM receiver).
It is a mid to late 1940's design and was first documented field use in the Korean War, and was in active use through the Vietnam War and continued to be maintained in US military warehouses until 1974. It was in use by other nations long after, most notably the Dutch military.
Additional information available on the blog
www.hamradioqrp.com/2021/01/a...

[@hb9dod]

Used the Radio Manpacked and in a Landrover in the Royal Netherlands Marines Corps until 1980.

[@dinosaurcomplaints2359]

A vietnam radio operator told me that every man in his squad had a length of copper wire and a fishing sinker attached to it. When they needed to make commo, everyone threw their sinker up over a tree limb so the cong couldn’t tell who had the radio. That was the first guy they would shoot, because he was the one to call in hell from above. Interesting impromptu survival tactic.

[@Chungustav]

I have a friend who was a radio operator in Vietnam. One of the few that lived. Man does he have some radio stories to tell

[@yougettingresults]

Thanks for the overview.

[@DustinPlunkett1]

Man that thing is a beast! I wouldn't be able to stand sitting next to that generator noise though. Then again, I guess in the field it wouldn't be as noticeable.

[@tonconnie]

That was my first rig. It was complete, even with spare tubes etc and the "knee morse key". Made some realy nice qso's with the an/grc9.

[@HamRadioQRP]

Yeah, mine still needs some adjustment. The receiver drifts while I send, so sometimes the reply is interesting to find.

[@StevenRosenberg]

I always wanted one of these!!!

[@chrollolucilfer1794]

Keep on posting bro

[@HamRadioQRP]

Plan to. Hope to get the hand crank generator working soon to do a field QSO with the angry nine

[@huawei97google55]

Это великолепно, бро! Отличный обзор военного радио. Вибратор звучит как волшебство. 👍 Таким образом мы имеем возможность перемещаться во времени назад. И это великолепно.

[@Steve-GM0HUU]

Very nice looking example and very interesting, thank you. Portable! Just slightly heavier than an FT-817! 😄 The method of setting the TX frequency reminds me of the (super accurate) BC-221 frequency meter. So, wondering if it uses same design idea? Good that you got on the air with it. It sounds nice (apart from the generator whine, perhaps).

[@HamRadioQRP]

Not too bad with headphones.

[@ElectronicsUSA]

I have a GRC-9 and love it - a super cool rig. At what distance away from the panel did the Geiger counter return to normal background level? Please post the video you made of your testing. Thanks and 73!

[@HamRadioQRP]

About 36" inches

[@StevenRosenberg]

If I recall, it was tough to find the dynamometer

[@HamRadioQRP]

I still see them for sale but the vibrator for the low voltage circuit has usually stopped working or is unstable. I tried refurbishing a couple of spares but eventually built a solid state replacement for the low voltage circuit in my dynamotor.

[@darrinpearce9780]

Great rig in fantastic condition. Alpha emitters are pretty safe, just dont eat the paint.

[@HamRadioQRP]

I have more video concerning the radiation after measuring with my own geiger counter. I need to edit and post. Almost half is Gamma, not stopped by aluminum.

[@troy3456789]

@@HamRadioQRP 😯

[@ElectronicsUSA]

@@HamRadioQRP I have a GRC-9 and love it - a super cool rig. At what distance away from the panel did the Geiger counter start normalizing again to background levels? Please post the video you made of your testing. Thanks and 73!

[@warplanner8852]

I may have missed it, but where did you say you got your radio?

[@HamRadioQRP]

Famous auction site e*ay The fellow had UPS store pack it... They didn't use any filler in the boxes and by the time it had gotten to me the parts and bags were mostly missing box. Yet I did receive everything. It's a testimony to the toughness of the equipment that it made across most the country as just raw parts bouncing around in trucks and still mostly worked when I received it.

[@HamRadioQRP]

Famous auction site

[@iridiumflare007]

Когда будет новое видео?

[@HamRadioQRP]

I have ideas for new vids, just can't find the time.

[@davidsonkofi858]

Explain the Morse code transmission

[@HamRadioQRP]

There were a few different partial conversations from different operators mixed in that video. They were just sending locations, names and club numbers. The code I sent was a request for a conversation along with my call sign. That's referred to as calling "CQ"

[@mohinderkaur6671]

Radium paint! yummy!

[@HamRadioQRP]

Minty

[@jeffdyer2393]

Very cool peace of history. Glad not to have to listen to the generator in my shack ha.

[@HamRadioQRP]

Amazingly, I've kinda gotten used to it.

[@otm646]

2:49 Who's giving you that advice? The Alpha particles emissions are harmless. As long as the paint is not flaking or you're ingesting the pain there's zero risk to you or anyone else.

[@hygwulf]

That's why is routine to cover it in clear enamel, to minimizing the flake off of the paint. Specially during operation, it's almost imposible not to touch the paint while operating the radio.

[@vanessahuman7607]

Isn't new technology great

[@HamRadioQRP]

Indeed. But sometimes we appreciate new technology more when we experience its predecessors. I started in the hobby with relatively modern rigs. I've enjoyed learning to use and repair radios that were amazing for their innovation of their time. I also learn more about radio and operating when using equipment that forces me to understand what I'm doing. This is my first radio with a separate receiver and transmitter. Older hams grew up with this but it's instructive to me. I don't personally know of another radio beyond the GRC-9 and its counterparts that could be supplied power by so many different and variable means. It could be powered by battery, hand crank generator, dynamotors supplied from 6vdc, 12vdc, 24vdc, 115vac and even a gas powered unit. The circuitry inside the radio dealt with simultaneous connection of a battery and hand crank generator, and operated the receiver on a very low current draw (for the time) of 500ma for filament and 200ma for the plate current. It wouldn't even power the transmitter section in phone mode until the PTT was pressed, to save power. If the battery was attached while using the hand crank generator it reduced the load on the person cranking. There were some very innovative people designing this stuff 80 years ago, using pencil and paper and their imagination. This is also the only transceiver I'm familiar with that can be used in the rain or float in a lake and still operate after pulling it out. I could go on and on about the design of the carry bag, or the fast deployment counterpoise, or the end fed antenna with disconnect sections for tuning with an attached frequency card, or the earbuds...