Comet CAT-300 Antenna Matching Unit - Ham Radio Review

[@ericinthebush1961]

I've had one of these units for a few years now, and love it to bits. It really works very well indeed. I use it at home and in the field. 73's from South Africa.

[@watersstanton]

Thanks for sharing

[@yt5bos]

Thank you for the review. Reflected power indicator needle needs to be calibrated on that unit.

[@watersstanton]

Yes it does. I noticed it after the video was published !

[@terryjwood]

Thanks for the review. We'll all miss MFJ! But I'll have to give a look at Comet products.

[@watersstanton]

Many thanks.

[@KD9ZHF]

I appreciate your videos, Mr. Waters.

[@watersstanton]

Thanks for your support.

[@davidportch8837]

Thanks Peter for another interesting video.. I always enjoy watching your channel. The ATU seems quite robust. I agree with you that the caps in the unit look well able to handle the stated power...

[@watersstanton]

Thanks 👍

[@Wretchedone69]

This looks well made.

[@watersstanton]

Yes

[@jimdavis5230]

I have a Capco SPC300 ATU which will match anything to anything. The Capco is built like a tank but has no metering. I therefore built a Brune bridge with forward and reverse power meters and connected it between the rig and the Capco ATU. I also installed a 1 to 1 current balun in the Capco for feeding balanced feeder and it works superbly.

[@watersstanton]

Yes I remember the Capco. The designer was quite a character!

[@justiceforall8574]

Certainly I share your enthusiasm for this product Peter so thank-you so much for showcasing this delightful unit.

[@watersstanton]

My pleasure!

[@kumasu]

I bought the MFJ version when I heard they were closing up shop, but I've never taken it out of the package. The ICOM 7300 is always able to match things up nicely.

[@watersstanton]

Thanks for info.

[@nateitkin8279]

It looks to be a very good unit indeed. Thank you for demonstrating it. The only downside is the 300 Watts. I bought a very nice MFJ 300W tuner and when I later wanted to use 600W, I had to buy more capable tuner. Unless the ham is absolutely certain he/she will NEVER want to run higher power, they should just start with a Palstar AT2K or similar and be done. That's what I wish I had done to begin with. I suppose this comment is more in the financial column than the radio column but I suspect a lot of CAT-300 buyers will end-up buying an AT2K or similar at some point.

[@watersstanton]

Thanks for sharing your thoughts.

[@brian.7966]

well done Comet, that looks like a great-looking Matcher, MFJ were always a bit tatty looking.thank you Peters,

[@watersstanton]

Yes a nice unit.

[@robduncan599]

Tks for the demo .

[@watersstanton]

You are welcome

[@neilbchilton]

Another reason for the inductor selector being split in the 80m and 160m bands is the Japanese band plan is separated there.

[@StreakyP]

When you are on PEP both fwd & ref should both be PEP to get the cross SWR right. That way you can leave the av/pep switch in whatever is your preferred position & still get a valid SWR reading.

[@Siskiyous6]

The lack of an accommodation for twin lead is a deal breaker for me. For the money I shouldn't have to add another piece of kit to use the doublet, which is the most logical multi band antenna.

[@watersstanton]

Maybe they will copy MFJ and put a 4:1 balun inside a new version. I prefer the flexibility and ratio choice of an external one.

[@l.a.2646]

Very nice instrument, I've had an MFJ 949c for as long as i can remember - that i bought used way back then( late 1980s?) This reminds me of my trusty 949e . I would imagine that this Comet should last as long. Glad that some companies are stepping up to fill the vacuum left by MFJ.

[@watersstanton]

Thanks for sharing.

[@splnail]

Thank You

[@watersstanton]

Welcome!

[@wd8dsb]

Any idea what size (physical dimensions) the coaxial power plug needs to be? This would be the plug that fits the jack that provides power to the meters light? No one appears to know the spec for the plug.

[@DavidCase-ov5uo]

Added comment.. manual tuning units can be adjusted with a noise bridge or vna instead of risking your finals or annoying other users..

[@watersstanton]

Yes.

[@DavidCase-ov5uo]

The thick meter bezel somehow makes it look dated but probably helps to protect the meter face.

[@mariemccann5895]

It would be good if the needle didn't stick. Wouldn't trust it.

[@frankmercurio6009]

Hi Peter. LoVE your videos. I’ve learned a lot from you. As a newer ham, does a manual antenna tuner do a better job than an ATU? I’m using the LDG z100a with my FT710. Thanks for your help. Frank W8FXM

[@watersstanton]

You are very welcome Frank

[@AnthonyJones-vk6xq]

Comet products as you know Peter are of a much higher quality, well worth the money.

[@watersstanton]

Agreed.

[@mariemccann5895]

Is that why the needle is sticking?

[@richardmills9831]

A far superior 300watt matcher than the300watt MFJ products ever were. I also feel that Comet Co-Linear antennas are better quality than Diamond products and it's why I'm pleased your company/sales group stock Comet products.

[@watersstanton]

Thanks for sharing

[@mindblast3901]

Got one there Great 73

[@watersstanton]

Great.

[@perryjones5500]

looks like the REF needle needs zeroing

[@watersstanton]

Yep agreed.

[@ivandubinsky1857]

I wonder where you would set the inductor switch for 60 meters operation?

[@watersstanton]

Probably 7MHz but I didn’t check that band.

[@cczinn7670]

This is a solid tuner I just wish they didn’t use the fluorescent coating on the meter face.. makes it extremely difficult to see for me although it has settled a bit since it was new, otherwise I love it!

[@watersstanton]

Yes, I have an eye problem but I coped. I know what you mean.

[@georgeholman6745]

Just a heads-up: Your link label describes a "Comet CAT-400"

[@watersstanton]

Thanks will update it.

[@georgeholman6745]

@@watersstanton 😉

[@Aimsport-video]

A roller inductor version with built in balun would sell well

[@watersstanton]

Yes.

[@leonvanderlinde5580]

I see the refelected meter is faulty. It does not go down to zero.

[@watersstanton]

There is a screw adjustment below fir zeroing. Now done.

[@adam-g7crq]

Hi Peter, I'm after a balanced Z match can you recommend one that's ok and doesn't cost a fortune. And covers from top band upwards.

[@watersstanton]

I have always gone the balun route. Your best bet is a used unit like KW match.

[@wilduc7302]

Lay-Out is nearly the same as my golden oldie Daiwa 419…

[@watersstanton]

Interesting.

[@nul153]

Have the same Daiwa, it works like a charm👍

[@rj2para]

Do you need to switch off the internal tuner before you use it please?

[@GoonyMclinux]

You can but some radios like certain icoms say not to, I bypass to an external for a decade and never smoked a radio so .....

[@Gw0wvl]

Yes of course you would 👍

[@davidwalle5025]

Good video I have the mfj turner

[@watersstanton]

Cheers.

[@Pioneer936]

Put the counterpoise on the antenna not the tuner

[@watersstanton]

No no no! If you connect an end fed wire to this tuner you MUST. connect the counterpoise as I indicated.

[@Pioneer936]

@watersstanton why would you encourage rf into shack

[@brianfields4479]

Very good instrument for sure. 73

[@watersstanton]

Thanks for viewing

[@Tishers]

MFJ made fine beginner projects. You just had to strip out the components and make a real bit of kit out of the chassis.

[@donnieking2610]

I love your videos are they a way to ask you a question kk4ekk Tennessee USA

[@watersstanton]

If it is about the video you can ask on this channel.

[@G1ZQCArtwork]

These Aerial matching units appear to be very good. I have an old MFJ manual which appeared to tune anything, until the Grey smoke escaped from the plastic coil former. So at 100 Watts into a bad non resonant Aerial, you can easily waste 75% or more of your power in the coils. Then I learned how to cut and install resonant dipoles and a 1 to 1 balun for the reactance. Unfortunately we get a lot of Winds in rural Lincolnshire, which tends to wreak havoc... Happy times, 73 G1ZQC.

[@watersstanton]

Thanks for sharing. A non resonant antenna has virtually no effect on ATU power transfer. Most of the loss is in the feeder and antenna radiation efficiency.

[@G1ZQCArtwork]

Yes but the power has to go somewhere, so is distributed within the ATU as heat.

[@Pioneer936]

@G1ZQCArtwork no it's not it's reflected back to the antenna at the tuner,any loss is in the feedline which can be very little depending on feedline attenuation even with a very high swr

[@Pioneer936]

@@watersstanton I remember a time when you said the same as @G1ZQCArtwork

[@mariemccann5895]

Wouldn't trust that meter with a sticking needle.

[@watersstanton]

Are you confusing “sticking” with PEP hold feature?

[@gavindouglas5581]

Not roller inductor

[@watersstanton]

Correct.

[@gavindouglas5581]

Ok my mate .from new Zealand Zl1gam on 20 metres 80 and 40.

[@GM5DDX]

No bypass tho so not as useful as the mfj

[@russpeed1]

HUH? It's called the On/Off button.

[@watersstanton]

There is bypass.

[@chopchop3464]

The British don't get excited

[@watersstanton]

Oh!