Search found 990 matches

by ChuckG
Thu Feb 14, 2019 8:33 pm
Forum: FM Radio
Topic: Optimod 2200
Replies: 3
Views: 209

Optimod 2200

Is misbehaving. Runs fine for days...but at some point the input, output and composite meters all pin full scale. When this happens the audio becomes very distorted. Removing audio input, the meters remain pinned full scale. Switching to "bypass" cleans up the audio, but does not unpin the metering....
by ChuckG
Thu Jan 24, 2019 6:09 pm
Forum: FM Radio
Topic: HT-10 APC issues
Replies: 12
Views: 652

Re: HT-10 APC issues

Mark Persons used to repair those by gutting the amplifer and installing a Broadcast Concepts module. Takes just a few hours and a fraction of the cost Take a look: http://www.mwpersons.com/tech-tips/FM/Harris-300-watt-ipa.htm Believe most of those IPA's in the HT-10 are repairable by Silicon Valley...
by ChuckG
Thu Jan 24, 2019 6:05 pm
Forum: AM Radio
Topic: Gates One Blows PA Fuses w/ Modulation
Replies: 26
Views: 1299

Re: Gates One Blows PA Fuses w/ Modulation

I don't recall seeing any on the ones or the fives. I've done the IPA drive measurement many times (scope across a quad resistor, ) and it's safe enough if you are careful. The control and IPA supplies are on but the RF supply should be off. The SX5 has unused thru the bulk head BNCs for making live...
by ChuckG
Mon Jan 21, 2019 6:48 pm
Forum: FM Radio
Topic: Harris HT-10FM freq change
Replies: 5
Views: 262

Re: Harris HT-10FM freq change

Must be the gap between the stub and whatever is around it that is relevant then. I can't find a drawing of the filter anywhere, but there must be some way to modify what you have if you could get the correct dimensions. The odd thing is...Harris calls for the stub to be longer when moving up in fre...
by ChuckG
Mon Jan 21, 2019 1:36 am
Forum: FM Radio
Topic: Harris HT-10FM freq change
Replies: 5
Views: 262

Re: Harris HT-10FM freq change

Can you just shorten the one you have? I'm not remembering what that part looks like.
by ChuckG
Mon Jan 21, 2019 1:32 am
Forum: FM Radio
Topic: Gotta love Westwood One
Replies: 2
Views: 166

Re: Gotta love Westwood One

I called the WOR network years ago after several weeks of double audio on a weekend car program. The Assistant there basically accused me of being a corncob pipe smoking, shoeless incompetent backwoods Wisconsin hillbilly who miswired the satellite receiver. Until the DoE, (who I have immense respec...
by ChuckG
Thu Jan 17, 2019 12:31 am
Forum: FM Radio
Topic: 100 OHM 100W resistor in Harris HT35FM PA Cavity
Replies: 10
Views: 553

Re: 100 OHM 100W resistor in Harris HT35FM PA Cavity

That's a non-inductive resistor. You should be able to change it to a tab-connector (also non-inductive) replacement without issues if you can't find the circular fingerstock connectors. Surplus Sales of Nebraska has them from time to time too.
by ChuckG
Tue Jan 15, 2019 11:35 pm
Forum: AM Radio
Topic: EZ Kleen Filters
Replies: 3
Views: 331

Re: EZ Kleen Filters

If those are the aluminum mesh filters, I put them in the trashcan and use either 3M Filtrete or Hog's hair cut-to-fit media, depending on the air velocity. Metal mesh sucked through a blower and into a power supply is something that won't happen twice.
by ChuckG
Mon Jan 07, 2019 9:36 pm
Forum: FM Radio
Topic: BE FM-5BS PROBLEM
Replies: 5
Views: 364

Re: BE FM-5BS PROBLEM

Ugh what fun. I wonder what sort of interface there is between the controller cards and the rest of the transmitter? Any chokes, feed-thoughs, filter caps, etc that interface the controller box to the rest of the transmitter? I've never seen this transmitter in the wild, so the most I can do is stan...
by ChuckG
Wed Jan 02, 2019 7:46 pm
Forum: AM Radio
Topic: Gates One Blows PA Fuses w/ Modulation
Replies: 26
Views: 1299

Re: Gates One Blows PA Fuses w/ Modulation

I just had to trade trucks and unloaded a big case of spare parts from my 2007 Ram that had not been opened since it was put there in 2007. It is not going in the new Ram. Many of the boxes, bags or parts are unreadable now after riding around for 10-15years. I've found that as soon as I start carr...
by ChuckG
Tue Jan 01, 2019 9:40 pm
Forum: AM Radio
Topic: Gates One Blows PA Fuses w/ Modulation
Replies: 26
Views: 1299

Re: Gates One Blows PA Fuses w/ Modulation

I am currently using the Infineon brand from Mouser, $6.50 each. They are working just fine in my Gates 5's. Are these the TO-220 or TO-3? TO-247 isn't it? . Last order I placed was 2~ years ago, looks like they have the VIshay brand now. $3.02 each. I may have to try a few of those and see...for h...
by ChuckG
Tue Jan 01, 2019 2:20 pm
Forum: AM Radio
Topic: Gates One Blows PA Fuses w/ Modulation
Replies: 26
Views: 1299

Re: Gates One Blows PA Fuses w/ Modulation

I've had them test OK with a 260 and still do funky things in service. I'm betting yours will test OK...as they operate OK until you push them hard..then they break down. Just mentioning it....you can get a "good" test result and still have failures in actual use. For the effort involved, I'd just s...
by ChuckG
Tue Jan 01, 2019 12:41 am
Forum: AM Radio
Topic: Gates One Blows PA Fuses w/ Modulation
Replies: 26
Views: 1299

Re: Gates One Blows PA Fuses w/ Modulation

The FETs associated with that fuse are drawing too much current. Replace them and check the IPA drive to that quad. The procedure is in the manual, you need a scope across a particular resistor.
Have those FETs been replaced in the past? It can be picky about manufacturer.
by ChuckG
Sun Dec 23, 2018 9:39 pm
Forum: AM Radio
Topic: LPB Output Transistors (SD-1407 Matched Pair)
Replies: 3
Views: 246

Re: LPB Output Transistors (SD-1407 Matched Pair)

Came across this but have never personally done business with them:
https://www.rfmw.com/Products/Detail/SD ... dB/314496/
by ChuckG
Thu Dec 20, 2018 9:03 pm
Forum: From the Trenches
Topic: "Help" desk
Replies: 11
Views: 744

Re: "Help" desk

Can you upload photograph or video of arcing and smoke?

You know he just wanted this to post on his cubicle wall lol.