Heathkit SB220 resistors

[Jimbo165]

I picked up a SB220 and during cleanup of amplifier the resistors on top of capacitors look like they got hot so I want to replace them . They are a 30k 7 watt resistor not sure of voltage required , there are 8 to be replaced. I googled them and nothing came up and have not been able to find these. Is there a replacement value I can install and not cause any problems with amplifier? Also what would cause these to get hot? Thanks Jimbo

 

[KF4HNF]

I picked up a SB220 and during cleanup of amplifier the resistors on top of capacitors look like they got hot so I want to replace them . They are a 30k 7 watt resistor not sure of voltage required , there are 8 to be replaced. I googled them and nothing came up and have not been able to find these. Is there a replacement value I can install and not cause any problems with amplifier? Also what would cause these to get hot? Thanks Jimbo

Hello Jimbo
you can use 10 watt resisters voltage doesn't matter on my SB-220 they are green but body color is unimportant. You should also change out the caps. and check for shorts.
Here's a link for the resistors they are 10watts but will work fine.
http://www.digikey.com/product-sear...t=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25.

73 Lawrence : KF4HNF

 

[Jimbo165]

Hello Jimbo
you can use 10 watt resisters voltage doesn't matter on my SB-220 they are green but body color is unimportant. You should also change out the caps. and check for shorts.
Here's a link for the resistors they are 10watts but will work fine.
http://www.digikey.com/product-search/en/resistors/through-hole-resistors/66690?k=&pv2=10&FV=fff40001,fff80482,40411&mnonly=0&newproducts=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25.

73 Lawrence : KF4HNF

Thank You for the info. Jimbo

 

[BBB]

This could be in your future. vvvv

http://harbachelectronics.com/shop/heathkit-sb220-sb221/es4sb220-filter-capacitor-block/

 

[wavrider]

jimbo as posted go the harbach route, upgrade full power supply including metering board, you will not be disappointed.

The power supply components in those old heathkits have pretty much reached their limitations of usage, just a matter of time before they start failing, with catastrophic results especially if you loose a meter.

Harbach kits are not hard to install and have added safety features like meter protection etc etc. you will want the full PS kit and also the keying circuit so you can key the amp with modern transceivers, in original circuit it is around -110vdc on the keying relay, todays modern transceivers can not be used with that high of voltage.

 

[BJ radionut]

http://harbachelectronics.com/product-category/heathkit-sb220-sb221/

Here's the link to Jeff's /W8CQ's webpage for the SB220 kits and items
All the Best
Gary

 

[WMS]

I restored my SB 220 using this Article
http://orcadxcc.org/content/sb220_compendium_va7jw_rev2.pdf