# Comm Spec AT-2B

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#### dshmel

##### Well-Known Member
Anyone order an AT-2B from Communication Specialists recently? I noticed their website only has lower power (30 milliwatt) transmitters listed under an R/C page. The AT-2B is 50 milliwatt.

Staff member
Global Mod

#### dshmel

##### Well-Known Member
Thanks. I found that link too and placed an order for one last week.What is strange is that the hotlink associated with the rocket photo no longer takes you to the rocket page.

I guess I will find out shortly if they still sell the At-2B or if there is just a glitch in their web site.

#### dshmel

##### Well-Known Member

... rest of list.

#### cwbullet

##### Obsessed with Rocketry
Staff member
Global Mod
I emailed the owner to ask.

Thanks

#### JDcluster

##### Well-Known Member
They have been updated. I bought the newer version from Wildman back in June.
He said that the frequencies can be changed, also have a longer antenna.

JD

#### dshmel

##### Well-Known Member
They have been updated. I bought the newer version from Wildman back in June.
He said that the frequencies can be changed, also have a longer antenna.

JD
Spoke to Randy at Comm-Spec. The AT-2B is no longer featured in their catalogue. It has been "replaced" with the RC-HP. Randy said that they can still make the At-2B as a special order item. Not sure if this accommodation has an expiration date (e.g. when they run out of parts?). My concern with the RC-HP is it's 30 milliwatt power output versus 50 for the AT-2B, and the the antenna is 13" long - but can be cut in half with a decreased range penalty. I don't know how important the extra 20 milliwatts of power is, but I have always had good luck with the AT-2B (except for when it is tethered to the nosecone of a cardboard rocket that comes in ballistic).

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#### cwbullet

##### Obsessed with Rocketry
Staff member
Global Mod
I received the same message. The new transmitter has less range but better durability.

#### Brent

##### Well-Known Member
I had a transmitter made for me for my Comspec receiver by another company that has posted on the forum before. Can't remember the name right now but the case screws together.

#### dshmel

##### Well-Known Member
I had a transmitter made for me for my Comspec receiver by another company that has posted on the forum before. Can't remember the name right now but the case screws together.
I am planning on getting an XLF 6v from LL Electronics, who said they could provide one in the Comm-Spec R-300A's range.

#### dshmel

the XLF 6v is a little spendy at $155+, but will fit in much smaller rockets. #### mpitfield ##### Moderator Staff member TRF Lifetime Supporter Global Mod the XLF 6v is a little spendy at$155+, but will fit in much smaller rockets.
I recall seeing a post on these transmitters a few years back. I just looked at their product offering and even the transmitter in the link below appears to be a good option. Heck 7 mile range, that is more than adequate for the majority of my launches, I am good with 5 for this transmitter. I am going to reach out to the manufacturer to see if they feel that this is a good choice for my application. If so I may pick one up to be used instead of my AT-2B transmitters in a 38mm MD nosecone, which is relatively tight.

#### cwbullet

##### Obsessed with Rocketry
Staff member
Global Mod
Com-Spec AT-2B has arrange of 50 miles in the air and 5 on the ground.

#### dshmel

##### Well-Known Member
Com-Spec AT-2B has arrange of 50 miles in the air and 5 on the ground.
The difference in Air/Ground specs is an important distinction. My longest recovery distance thus far using an AT-2B is 2.18 miles from the launch site. The signal was strong in the air but dropped considerably when the rocket landed - which is to be expected of course. I had a very very faint signal at that 2 mile distance. It is important to remember that polarity matters, rotating the antenna/receiver can make a weak signal discernible. I would imagine the 5 miles on the ground is under ideal conditions with little to no terrain.

#### crossfire

Why did Com Spec. stop making the transmitter that had the black plastic box?

#### dshmel

##### Well-Known Member
Why did Com Spec. stop making the transmitter that had the black plastic box?
I didn't really press Randy for too many details but he mentioned the fact that the new transmitters are more robust (waterproof case) and are smaller. The RC-HP is also cheaper at \$75. In additional to 3 AT-2B's I also own a PT-1B, which has the same case as the new line of transmitters. I don't care for the long antenna (18") and the 1 milliwatt output is fairly weak. I have only used it a few times because of those limitations. I like the case of the AT-2B because it is easy to tape to a shock cord. I also like the shorter 10" antenna.

#### crossfire

I like the AT-2B also. Maybe Randy needs to know if more chime in from rocketry that they like the AT-2B better.

#### ksaves2

I like the AT-2B also. Maybe Randy needs to know if more chime in from rocketry that they like the AT-2B better.
One problem might be some part or parts are out of or going out of production. Might not have anything to do with sales or popularity. Kenwood Radio was blind sided when an essential part for their APRS tracking radio D7A(g) went out of production with
no warning. Took them something like 2 to 3 years before they got a new radio on the market the D72A. Now I hear they are going to come out with a second GPS tracking radio and perhaps that might be a hedge for future issues. Kurt

#### Brent

##### Well-Known Member
I was told that you could still get the AT-2B by request. I called Communication Specialties and I tried to get an AT-2B transmitter from them. They told me that they would call me back. I told them that I was not happy with the range of their new transmitters. I did not tell them this but the last time I used it I got interference or the range just plane sucked. I located the rocket but that was because I new the direction to walk. Anyway never heard anything for a couple days so I emailed them. Randy replied that they would not make any more.

#### KenRico

##### 'Just the Tip'
I just destroyed one that Randy had just fixed .. asked him the best replacement and he sent me the link to RC-HP also.

Am watching this thread with interest .. have an expensive receiver idle.

Kenny

#### dshmel

##### Well-Known Member
I just destroyed one that Randy had just fixed .. asked him the best replacement and he sent me the link to RC-HP also.
It would be unfortunate if Comm-Spec did discontinue the AT-2B altogether (as a special order). That was/is my "go to" transmitter. I had LL Electronics make me an XLF 6V in 222.990 MHz for use with my Comm-Spec R-300A. However, they purposely made it 222.995 MHz with the assertion that I could tune it in better with my R-400A. Only issue is that I don't have the Comm-Spec R-400A (for falconry), I have the R-300A. I am currently working with Lauren at LL Electronics to see if their unsolicited solution of sending me a transmitter made for 222.995 MHz is/would be better than 222.990 MHz.

#### Wayco

##### Desert Rat Rocketeer
It would be unfortunate if Comm-Spec did discontinue the AT-2B altogether (as a special order). That was/is my "go to" transmitter. I had LL Electronics make me an XLF 6V in 222.990 MHz for use with my Comm-Spec R-300A. However, they purposely made it 222.995 MHz with the assertion that I could tune it in better with my R-400A. Only issue is that I don't have the Comm-Spec R-400A (for falconry), I have the R-300A. I am currently working with Lauren at LL Electronics to see if their unsolicited solution of sending me a transmitter made for 222.995 MHz is/would be better than 222.990 MHz.
The Com-Spec 300A will not tune to the 5 khz frequency. I also bought an LL Electronics TX, 224.115, after talking to Lauren. She said to call her when I got it and she would walk me through the tuning process. Received it three days ago and yesterday called her. We tried several times, even got Louie the owner envolved, no can do. I'm sending it back for another unit with 224.110 Mhz as it's frequency.

#### dshmel

##### Well-Known Member
The Com-Spec 300A will not tune to the 5 khz frequency. I also bought an LL Electronics TX, 224.115, after talking to Lauren. She said to call her when I got it and she would walk me through the tuning process. Received it three days ago and yesterday called her. We tried several times, even got Louie the owner envolved, no can do. I'm sending it back for another unit with 224.110 Mhz as it's frequency.
I will be sending my XLF 6V back to LL to be remade in 222.990 MHz (instead of 222.995 MHz). Lauren wrote: "I was unaware until recently that the R-300A does not have the capability of a fine tune."

I will also advise them of the opportunity to market their transmitters to rocketeers using Comm-Spec receivers. I am not sure of the market share potential, but with Comm-Spec discontinuing the AT-2B transmitter, I imagine many Comm-Spec receiver owners may want a high power option. The AT-2B was claimed a "50mW power output into loaded 10", easy to replace, antenna. Range: 5+ miles on the ground, 50+ miles in the air."

Does anyone know the power output of the XLF 6V? The new Comm-Spec RC-HP transmitter (replacing the AT-2B) has a 30 milliwatt output and claims to have "Up to 10 Mile Range." LL Electronics says the XLF 6V has a 30 mile range.

#### dshmel

##### Well-Known Member
Sent my XLF 6V back to LL Electronics to be remade. I will let everyone know how it works after being tuned to the correct frequency for my R-300A.

#### dshmel

##### Well-Known Member
Update: So I received my XLF 6V a couple of weeks after I posted this update. I flew it successfully at a handful of launches. It decided to die on my at AIRFest three weeks ago. I have sent it back to LL for warranty service.

Sent my XLF 6V back to LL Electronics to be remade. I will let everyone know how it works after being tuned to the correct frequency for my R-300A.

#### ksaves2

Errrrrrr.... I think being strapped to a rocket is a bit more stressful than being attached to a hawk.:wink:
That said, I can't recall many posts about problems when flown with/in rockets. Maybe your
experience was a fluke that they'll fix for you. You might want to look closely and see if
they repair your tracker or simply send you a new one. Kurt

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#### dshmel

##### Well-Known Member
Errrrrrr.... I think being strapped to a rocket is a bit more stressful than being attached to a hawk.:wink:
That said, I can't recall many posts about problems when flown with/in rockets. Maybe you
experience was a fluke that they'll fix for you. You might want to look closely and see if
they repair your tracker or simply send you a new one. Kurt
From the LL web site:

"HIGH POWER TRANSMITTERS

High Output Transmitters push the limits of battery technology, packing the largest punch into the smallest package possible. Tuned to continue working in the freezing cold or the blistering heat and resistant to impact and vibration up to 50,000 g's, these units offer both reliability and power."

:wink:

Considering the fact that the transmitter was not involved in any incident, I can say with high certainty it did not experience >50,000 g's.

This particular transmitter was sent back and remade to the proper frequency (the one that I specified when ordering) so that it would work with the Comm Spec R-300A. Perhaps that process made is susceptible to failure (?)

I wait to hear from them after they complete their diagnosis.