I spent the New Year eve going over the Dentron CLipperton L I bought at the Indy hamfest in July. Inside was pretty clean, but the design looks like a prototype! Think that is just older Dentron. It included two power supply boards, but the one inside looks new. Looks like it has had the 10M mod. Generally looks good inside. I vacuumed inside but there was not a lot of dust. Has two 10kv disc caps off the output to the PI network, schematic shows one.
It came with 3 old tubes and 2 new Taylor tubes. One of the old tube had the plate wire broken, see pix. One has pieces of glass loose inside, see pix, I installed it but would appreciate comments if that is ok. I installed the two new Taylor tubes in the top two positions.
Comments before I power up?
I hope to use this in my new station location when I run the coax to the library from the study area in the upstairs hallway.
Leroy
Be sure to listen for my beacon on 28.278.8 MHz
I don't see any pix, but Denny sold a lot of Clipperton-Ls and I think I've looked at about 20 of them over the years. Almost no two were exactly the same (factory changes without updating documents).
I hear 572Bs aren't what they used to be, so possibly all bets are off on these tubes, even if they're new. But RF Parts honors their warranty and if you have a bad tube they'll replace it for free.
I'd fire it up and try it. I guess you know it hasn't a tuned input, so some solid state rigs may not like the load much; it was designed to be used with tube transmitters having tunable output stages.
A government which robs Peter to pay Paul can always depend on the support of Paul.
Steve; It did come with a tuned input module, something like a CM-1 and it is in an aluminum enclosure with wires to select different bands. Looks like it is meant to go inside. My IC746 does have an ATU, would that match it or is the input really wild impedance?
Friend in the RCA club has a wattmeter/dummy load that I will get in January, but I would like to just power it on to see the HV and tubes are ok.
Pix in second post, for some reason they would not upload to the first post.
Leroy
Be sure to listen for my beacon on 28.278.8 MHz
I didn't know about the external tuned input...never saw that so I'm not sure what it is.
Your rig might drive it fine, why not try and find out? The advantage of a tuned input is mostly to make the exciter work better; the ATU might help do that.
A government which robs Peter to pay Paul can always depend on the support of Paul.
Looking at that photo of the "so called" CM-1, I think it is a homebrew version of one. I could be wrong. Most CM-1 units were a stand alone external input matching unit not ment to be put inside the radio itself. The multiple colored wires you see are to select each of the bands. They are connected inside to relays that select the proper input coil assembly for that band. As I recall the actual Dentron unit had a bandswitch that you would set to the same bad as the amp. I am pretty sure what you have there is a homebrew version of a CM-1. You'll need to do some improvising now. SOME Clipperton amps did have factory tuned input circuits and they resemble the ATI-6 board made by Dentron.
Definitely home brew, but nice enough construction. The instructions describe this as a low pass filter to reject harmonics of older tube transmitters.
Originally Posted by W1QJ
Looking at that photo of the "so called" CM-1, I think it is a homebrew version of one. I could be wrong. Most CM-1 units were a stand alone external input matching unit not ment to be put inside the radio itself. The multiple colored wires you see are to select each of the bands. They are connected inside to relays that select the proper input coil assembly for that band. As I recall the actual Dentron unit had a bandswitch that you would set to the same bad as the amp. I am pretty sure what you have there is a homebrew version of a CM-1. You'll need to do some improvising now. SOME Clipperton amps did have factory tuned input circuits and they resemble the ATI-6 board made by Dentron.
Leroy
Be sure to listen for my beacon on 28.278.8 MHz
That amp appears to have the front phenolic wafer that was used with the later internal tuned input board. I have NOS bare ones available.
The caps in the RF section are replacements as are the PS caps so you have a good chance it works but its a poor performer on 160 and the low end of 80 without mods. Also pull all the parasitic suppressors and measure the resistors. If out of tolerance replace with 47 Ohm Ohmite OY series.
With a bit of effort and little $$ it can be good workhorse amp.
Bringing up Dentron CLipperton L....My first amp
Originally Posted by W1QJ
