Upcoming Activity

[Charlie Young]

On the near time horizon, we are going to the Ripley hamfest this Sunday.  Riding up KD8GWH, WB8CQV and W8IW.   Should be a fun day.  Looking forward to it. 

In two weeks we will go to Hamvention in Xenia, traveling with WB8CQV, K8WVA and KD8GWH (taxi driver). This will be a good test of my ongoing recovery.   I am in better shape than last year, plus we will have a cart this year.  It will make the flea market easier.   I am not looking to acquire anything, but am always on the lookout for special amplifier parts to support my repair and construction activity. 

ZL1RS will be on from A3 Tonga on 6M EME the Xenia weekend.   Not seen a detailed op sked yet from him.  Hopefully I can be QRV on one of the low degradation nights he is there. Fingers are crossed we can work it out.  I will not attempt to operate my EME station myself remotely..  It would probably be OK, but I like to monitor the amplifier locally. 

The big W9DR amplifier has so much reserve capacity, once we commission that , it would probably be OK to run  unattended if need be, but I have no plans for that.  It will be a while before this is commissioned, I have some repair jobs for others we have to tackle first.  I may wheel it into the shop for a more detailed inspection prior to Hamvention, in case I find something that is needed .  

Here is a good time to clarify my intent and philosophy regarding big power.  I have several amps available that will do that.   This W9DR amp is one.  The tube is capable, with 5000 watts plate dissipation.   For example, if the amp is 60% efficient, to get 1500 watts out  would require running 2500 watts plate input power. At 1500W output, the tube would be dissipating 1000 watts in the tube plate.  This is only 20%  of the tube max dissipation rating. 

This might seem overkill, but on EME with one minute transmit cycles,  the tube should last forever.  Currently, I can buy a 3CPX5000a7/YC-156  for less money than an 8877.   I have already toastsd 2  8877 tubes in my 6M amp when it was only 51% efficient.  Now it is 64% efficient after redesign and I have not lost a tube since.   Still, the YC-156 will run much cooler and thus the tube should last longer.  This converted Ameritron is capable of exceeding 2KW output, but this is hard on the 8877 tube.  I would rather not have to worry about the tube getting cooked. 

For the same reason as above the YC-156 makes a great HF amplifier.  I could put the K8KT Green Machine  on HF running 1500W out and likely never have to replace a tube. 

Some ops are running a 3CX3000 to get reserve capacity on HF and 6.   On 6M EME I find it is common among the bigger stations.  The 3CX3000 is a relatively low gain tube, so it takes some drive power.   Most folks who want to run power use a driver amplifier between the rig and amp.   There are a lot of SB-200 or amps of that power level  being used as drivers .  I once saw a contest station using a 3CX3000 on every band, and he was using an intermediate driver amplifier on each one.   Op is SK now.  

With this YC-156,  the rig as a driver is sufficient for all options one would want to pursue. My intent is to run legal and enjoy a tremendously long tube life of EME.    8877 tubes are expensive.

It is just like driving a Ferrari.  Restraint by the operator is needed 🙂.   

73 Charlie N8RR

[Larry Fravel]

Good and true analogy at the end Charlie.  Good to see you back on the reflector and getting out and about.  Please don't over do it.

73

Larry k8YYY

 Truth is like the sun. You can shut it out for a time, but it ain't goin' away. 
–Elvis Presley

--
You received this message because you are subscribed to the Google Groups "WVDXA DX Reflector" group.
To unsubscribe from this group and stop receiving emails from it, send an email to wvdxa+un...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/wvdxa/CY5PR11MB6284BEFC188A9901CA972B13D8322%40CY5PR11MB6284.namprd11.prod.outlook.com.

[Rick Robinson]

Been working on the spaces and related stuff for the past week or so. As always we'll have you a chair and plenty of water and shade. My understanding is Verizion has a tower across from the track. Just in case if you need connectivity. So glad you are doing well. 

To view this discussion visit https://groups.google.com/d/msgid/wvdxa/CAE%2BgwqZ43QVHm7BNsHuBCWsnmKND%3DaVnKPP7oePCYaMJHDTgOQ%40mail.gmail.com.

[Bob Anthony]

Chas, good to see you on the Reflector. Hope you are doing good as it looks. Have a great time at the hamfest and don't over do it 

W8om (Papa November) 

To view this discussion visit https://groups.google.com/d/msgid/wvdxa/CALvs4h-S%3DUOwR18LWkF%2BBGkcdiRHu%2B54CHZAdWUO_x41ZNywKw%40mail.gmail.com.